#343 – The evolving role of radiation: advancements in cancer treatment, emerging low-dose treatments for arthritis, tendonitis, and injuries, and addressing misconceptions | Sanjay Mehta, M.D.

Hey everyone. Welcome to the Drive Podcast. I'm your host Peter Attia. This podcast, my website and my weekly newsletter all focus on the goal of translating the science of longevity into something accessible for everyone. Our goal is to provide the best content in health and wellness and we've established a great team of analysts to make this happen. It is extremely important important to me to provide all of this content without relying on paid ads to do this. Our work is made entirely possible by our members and in return we offer exclusive member only content and benefits above and beyond what is available for free. If you want to take your knowledge of this space to the next level, it's our goal to ensure members get back much more than the price of a subscription. If you want to learn more about the benefits of our premium membership, head over to peterattiamd.com subscribe My guest this week is Dr. Sanjay Mehta. Sanjay is a radiation oncologist at St. Joseph's Medical center in Houston, Texas, where he's been in practice for more than 20 years. I wanted to have Sanjay on the podcast to talk about all things pertaining to radiation oncology, but also the history and some of the misconceptions around radiation exposure and radiophobia. We talk about some of the very interesting applications that I only learned about recently that are very common outside of the United States that involve low dose radiation to treat inflammatory conditions and athletic injuries. Now, of course, those of you who are interested may recall that because this podcast is called the Drive, I do occasionally talk about cars. And given that Sanjay and I have a shared passion for them, and in fact that's how Sanjay and I met, we do end this discussion with a little bit of a deep dive into cars. But of course, back to the main point of this discussion. We talk about the evolution of breast cancer, including the shift from radical mastectomies to more conservative approaches like lumpectivity and sentinel node biopsies. We talk more broadly about the role that radiation plays in modern oncology, how doses have changed and how advancements in targeting tumors while minimizing damage to surrounding tissues have rendered side effects much more rare, certainly more rare than they were even 20 to 25 years ago. Sanjay talks about the role of low dose radiation for inflammatory conditions such as arthritis and tendonitis, and how this approach is more widely used outside of the US and why it's his hope and mine that becomes more adopted here in the US we speak about the history and misconceptions of radiation exposure, including radiophobia, nuclear accidents and early uses of radiation. So without further delay, please enjoy my conversation with Dr. Sanjay Mehta. Sanjay, welcome back to Austin.

Thank you, Peter. Pleasure to be here.

I think this is the first time we're together not driving, right?

I think so, yeah. That is true.

I don't know. Somehow we're going to resist the urge for most of this discussion to not talk about cars.

Don't want to bore your audience.

I know it is called the drive.

This is true.

So I feel like we will reserve the right to have some automotive discussions at the end for listeners. Sanjay might be one of the most knowledgeable human beings on cars. He's also a very dangerous friend to have because he's always the bad one on the shoulder when you're contemplating a new set of wheels or a new something for your cars. But in his other life, in addition to being the founder of MD Motorheads. Right?

That's right, yeah.

Which is a Facebook group of doctors who are gearheads.

We're about to crack 3,000 members. It's exploded. Yeah.

That's awesome. So shout out to MD Motorheads. You're also a radiation oncologist, which we also spend some time talking about.

Right.

I guess we thought it would be a really fun idea to do a podcast for a couple of reasons. One is just the bread and butter of what you do as a radiation oncologist is a bit of a black box to many people, myself included, if I'm going to be completely truthful. Even training in surgical oncology, I feel like I had much more familiarity with the medical side of oncology than I did with the radiation side of oncology. So for myself, for the audience, I think it would be wonderful to understand more as it's a field that has evolved a lot. I'm guessing the last 25 years has seen a lot of change.

It's one of the youngest fields, too, in that respect. It's not steeped in some of the traditions that surgery and medicine are. So, yeah, it's a new field, highly evolving, very rapidly, and the technology has changed so much just in really in the last decade or two. It's pretty incredible.

Just out of curiosity, when did it become its own discipline, its own set of boards and everything like that?

As a kid and growing up in Houston, some of my family friends were radiologists. And I remember just like a probably an elementary school kid, that some of them were talking about radiotherapy. And they were. These were diagnostic radiologists, who at the time, CT scanning was pretty new in the 80s, prior to that in the 70s, and then prior to that it was kind of just a fellowship. Radiologists would have a Cobalt 60 machine that they would train on for a few weeks and you do a few easy calculations and you do some crude treatments. But it really started, it came into its own starting in the 70s and really more into the 80s. And that's when it became its own discipline. And the ACR had a separate carve out. And so our residency training is completely independent of diagnostics now. So we just do. It's an intern year followed by four years of radiation oncology with a little bit of overlap, but not a lot of diagnostic training at all. Just because there's so much to do just on the therapeutic side.

Got it. I had no idea that it was that new. And in terms of medicine, that's obviously like very new. The second thing that I wanted to talk about on the radiation front is this idea of using very low dose radiation to heal injuries. I think that while people will be incredibly interested to understand the ins and outs of radiation oncology again, given the ubiquity of it in treating people, I think a lot of people are going to be very interested in this idea that why aren't we using low dose radiation more to heal some of these nagging orthopedic injuries that people have? And of course we'll go far down the rabbit hole on that. But I don't think we can have this discussion without giving people some understanding of what radiation is. And I would like us to do it in a way that's both rigorous enough that we can really get into some of the science of this, but also get into it gently enough that people that maybe don't remember high school physics well enough can come along for the ride and not get lost. But once we get into grays and Millie Sieverts and all that stuff, I want everyone to be fluent when we start talking about doses.

Right, right, right. Radiation itself, the term itself has got a bit of a negative connotation, but basically it's part of the electromagnetic spectrum. So we have everything on the one in the range of increasing energy of photons, which are just particles of light. On the one end you have radio waves and microwaves, and the other end you've got infrared and, excuse me, you've got ultraviolet, and then you get into X rays and radio waves. And in the middle of all that is the visible spectrum. So when you see, I'm sure everyone's seen the graphs where you've got the rainbow, red, green, blue that we can see, the human eye can only perceive A tiny little narrow spectrum.

These are wavelengths.

These are actually wavelengths and energies which are the very low end energies. You have things like radio waves in that situation. Both radio waves and microwaves are what they call non ionizing. And I know you've talked about this on some of your previous podcasts. I know you had a really good one with Atari Walla from Prenuvo. It was really nice in depth discussion. But essentially the bottom line is that the low energy stuff that is non ionizing cannot damage tissue. And that goes all the way up to visible light. Then when you start going to the higher energy X rays, that's when you get both X rays as well as ultraviolet light and then the higher particle stuff. But basically the higher you go in the energy and the energetics of the particles, the more likely exposure to these packets of energy are going to cause damage to your DNA.

Why is it that the shorter the wavelength. Because that's what's changing as you go from radio waves to microwaves to visible waves to ultraviolet. Why is it that as the wavelength gets shorter, the energy gets bigger?

Yeah, I'm not sure what the reason is. They are inversely proportional to each other. I don't know that. I guess I'm probably not enough of a physicist to answer that question precisely. But having said that, that is the characteristic of this. And in doing so, that's one of the big reasons why all the fallacies about your cell phone giving you brain cancer and all are just that. They're fallacies because even having a cell phone on your ear for hours a day, it's non ionizing radiation. And standing too close to a microwave oven, again, non ionizing radia that cannot damage your cells.

The radio wave is too long.

That's right.

The microwave is too long. It doesn't have the energy. You can stand on it all you want, it can heat, but it can't damage.

Correct. It can excite the molecules, but it won't actually eject an electron, which is what would cause an ion to form, which is why it's called ionizing. And that's where we deal with on the. I'm on the therapeutic end. So diagnostic radiologists deal with lower energy X rays than we do. The very high energy X is what we use in our linear accelerators to treat cancer. So that's the big difference. There is kilovoltage versus mega voltage. But all of these are ionizing.

Okay, so let's talk about how these are measured. How do we quantify them? Because people on the podcast have heard Me talk about this. I suspect we talk a lot about calcium scores and CT angiograms and PET ct. I think the frequent listener will have been somewhat familiar with how we talk about how to dose those things.

So radiation dosage, there's a couple of different terms that we talk about. The main one we talk about when we're talking about patient treatment is the unit called the gray, and that's an SI unit that essentially is joules of energy per kilogram of tissue. So that's what they call absorbed dose. So that's in tissue. Whereas when you're talking about exposure in the general. In the air, and just in general exposure, it's in the air. We usually use the term sievert for that. And actually both those terms for the most part are equivalent. It's just that the sievert itself will take into account if you have different types of X rays, different qualities of X rays that have different degrees of potential to be ionizing, that they have a quality factor you multiply it by. But for the most part, we use the term gray when we're talking about. For example, when I treat a prostate patient, they're going to get somewhere between 70 and 80 gray, but it's fractionated into small daily doses as to be tolerable for the body. And then when we talk about millisieverts, like we're going to. That's really just a measure of exposure, not absorbed dose in tissue per se.

What's the relationship between a gray and a millisievert? Is it a one to one relationship?

Yes. A gray and a sievert. Technically, if anyone's kind of old school, you listen to older stuff, you heard the term rads. A lot of people have heard of rads. So 1 rad is equal to 1 centigray. 100 rads is a gray. It's just an SI unit versus the old terminology. And a sievert is the equivalent, only it's in air, not in tissue.

But a sievert is a gray, Correct?

Correct.

So when you give 70 gray, you're giving 70 sv or 70,000 millisieverts over the course of the treatment.

That's correct.

Okay. Just so people can kind of anchor this to things that are familiar, living at sea level exposes us to 1 to 2 millisieverts of ionizing radiation a year.

That's exactly right. At altitude, it could be double that.

That's right. If you live in Denver, it's easily double that or triple that. Correct. Just another thing for comparison. A Pilot who spends a lot of time traversing the north pole, which is typically how they're going to fly. They're not going to go all the way around the center of the earth. Might get another 3 or 4 millisieverts.

Quite a bit. Quite a bit. That's right. Per trip, actually. So that can add up. And I was actually talking to a pilot friend about this. They don't really have any limitation in terms of total exposure that requires them to be taken out of the air. A lot of them, they're forced to retire at 65, I think, is the commercial requirement, but they don't really monitor the actual exposure to that level. I think the reason they don't really use that as a limiting factor for the amount of work is really just that even though they get a higher dose, there's been no proven increase in cancer in those types of populations, even in flight attendants or anything like that. The same way that people in Denver and the people here in Texas don't have any higher incidence of cancer.

Now, the NRC recommends that a person not be exposed to more than 50, I believe, 50 millisieverts of radiation in a year.

Correct.

Now, someone like me, that's easy, unless I'm out there getting a lot of diagnostic radiology or, of course, undergoing therapeutic radiation treatment. But for someone like you who has to set patients up or one of your techs, Are you guys approaching that level of exposure?

Not at all. And so it depends on what type of radiation we do. Now, typically for our external beam machines, we're doing it all remotely from behind, behind a shielded wall. So the vault in which the machine is placed is custom built just to shield, based on the angles that the machine can move through. If there's, like a direct angle where the machine is hitting a wall, that wall has to be built 10 times thicker than the walls where the beam can't reach. So essentially, our dose when treating remotely is close to zero. So we keep film badges. And it's almost become kind of a joke that when we're not doing brachytherapy, which is dealing with actual live radioactive sources, our exposure is super low, almost negligible, really. But back when I was in residency doing a lot of gyn implants and things like that, where you're putting cesium or iridium actually into the body cavities, and you're actually up there putting it in. Up close, we had a ring badge on. And as a resident, we'd rotate every month, but if we didn't rotate some of the Faculty actually got pretty high doses.

Any idea what the sequelae of that was?

I know of a couple of folks, the ones who did a lot of GYN therapy, especially in the older days, we're talking about in the 80s and the 70s, where you could actually see dermatitis on their hands from doing that, just from the hand exposure. One of my faculty members actually had a giant cell tumor of the bone in her finger. And again, this is after decades and decades of doing it. It was a benign growth, but that was a real thing. There's a lot of data out there on especially people who were dealing in X ray for dentistry and stuff like that back in the day when they didn't have shielding or anything like that, that they would get dermatitis. The most common thing you'd see is skin irritation in that sort of situation, dermatitis and even some chronic flaking and things like that.

So let's talk about some types of X rays that people are familiar with and give a sense of radiation dose. And I'm also curious as to how much this depends on the size of the individual. In other words, does a person that is larger receive more radiation for this same test like a chest X ray?

They certainly do because you have to use more energy to get into a larger person. Having said that, there's two different things here, because in what we normally deal with when I'm talking about dose to a tumor is the dose actually at that spot versus a whole body dose, which is a very different metric. And so for someone who I'm treating with say eight weeks of radiation for prostate cancer, their Prostate may get 80 gray in 1.8 to 2 gray fractions per day. But that's literally only to a small volume, roughly the size of the prostate gland itself. And when you even get just a few millimeters away from that, that dose gets cut in half. And then it's exponentially lower because the intensity of the radiation varies with the square of the distance. So as you get even a couple of feet away, that goes down significantly. But typically a patient who is getting 80 grays, if 80 gray was a whole body dose, that would obviously be lethal. But the whole body dose is more like a few milligray in that sort of situation. So we typically don't see full body sequelae or anything from doing even the heavy duty diagnostic treatment. Now for the CT scan, we almost consider that negligible in our area because again, I'm dealing with mega voltage, high dose cancer killing radiation. And so when they get a CT scan which is gonna be just a few millisieverts or milligray. That's almost considered rounding error versus what they're getting to the tumor.

But let's take something like a chest X ray. So chest X ray people should anchor to this idea for what it's worth, and we can come back to this. NRC says, hey, limit your annual radiation to 50 millisieverts. You'd got 2% of that just being alive because you happen to go outside and be exposed to the sun. So the other 98% might come through flying diagnostic. Let's say you fly a lot, that might get you up another 10%. So let's talk about a chest X ray. You got a cough, you go to your doctor, they do a chest X ray. That's how many millisieverts for a normal sized person.

Normal sized person, it's a fraction, is probably less than 1 millisievert actually. So it's significantly. It's something that, where people who are concerned about things like diagnostic mammograms and all, every year you're still Talking about maybe 1 millisievert, even a little bit less than that with some of the newer machines. You're in a zone where there's a principle we talk about. It's called Alara A L A R A, which is as low as reasonably achievable. And that's been the mantra for our radiation safety people, the Nuclear Regulatory Commission and whatnot, that you want to keep things as low as possible. But having said that, when you're talking about numbers of less than 50 millisieverts, that's kind of an arbitrary number. I should have maybe gotten a chest X ray when I had my cough last time, but I just don't want to do it. I don't want the exposure. But it's so minimal in terms of biologic effect that we really don't even really worry about those, even if it's getting one of them a month or so. And a big reason for that is a lot of these numbers, especially the 50 millisievert number, is extrapolated from higher exposure rates. There's something called the linear no threshold model, or lnt, and that's been written about extensively. And that's what we're all taught in radiobiology and residency. One fourth of my radiation training and residency was actually radiation biology in addition to clinical oncology and radiation physics. So the linear no threshold model is what states that we know based on all the data from nuclear fallout from Chernobyl, from Three Mile island, of course, from Hiroshima, Nagasaki, from the bombs, that at a certain dose exposure, there's a certain risk of developing a cancer or any other endpoint, whether it be dermatitis or bone marrow suppression. There's all these numbers are well sorted. But when you try to extrapolate lower, so you take maybe say a dose of one full sievert, the thousand millisievert, and you start extrapolating that lower and lower to where you're looking at 100 or 50 millisieverts. The linear model assumes that there's some level of damage even at those lower levels. But in reality there's actually a threshold, the lnt, which is linear. No threshold has actually been proven to be actually erroneous. And so at very low doses, it's actually been shown that there's almost no incidence of any sort of biological damage. And there's also, it's controversial, but there's animal studies showing there may be a hormesis effect at low, low doses like that.

Tell people what that means because that's obviously going to come back later in our discussion.

Regular listeners of your podcast know all about hormesis and you talk about in the exercise realm and cold plunges and saunas and whatnot. But the whole idea is doing some degree, a small amount of cellular damage when the body repairs that it actually comes back stronger than it was without the exposure in the first place. And in animal studies, they've actually shown at very low doses, we're talking about single digit millisieverts here that they've seen in mouse bones, for example, decreased osteoclast and increased osteoblastic activity, so the bones actually heal quicker. Some of the soft tissue as well has been shown to actually recuperate, much in the way you see in hormesis from other causes. And that's not something that we're claiming is widely accepted, but there is a lot of data showing that that is certainly a possibility, which goes against this classic LNT model and the LNT model itself. The guy that won the Nobel Prize for it in the 1940s did this all on fruit flies, and his work was disproven over the years after that. And so a lot of this low dose radiation safety stuff we have is certainly a noble goal to keep the dose as low as possible. But when we get down into these millisievert range, I think that they're probably a little bit overblown in terms of the actual negative effects on the human body.

When I think about where, for example, Something like a CT angiogram used to be, that would easily have exposed a person to 25 millisieverts. To do a CT scan of the heart, you're doing it slowing the heart down, getting the contrast in there, et cetera. Today, the really fast scanners, the best of the best scanners are somewhere between 1 and 3 millisieverts for that same procedure. I certainly favor having patients getting a scan with that. Acknowledging, though, that I don't have amazing data to point to to say that the 25 millisievert 1 versus, just to make the math easy, the 2.5 millisievert 1 tenfold difference poses any difference in risk.

Exactly.

How do you think about that? What would be your confidence in saying that 2.5 is not actually better than 25 from a cancer risk standpoint?

So, again, going back to that Alara principle, there's not a whole lot of data at these levels. I certainly would strive to keep it as low as possible, which is what that mantra says. But I would go with the machine that has the best resolution. And if 25 is, if the radiologist tells me that that image is significantly better than a 2.5 millisievert exposure. Some of the older machines are just less efficient. You may get a better image with the lower dose, I think the dose is pretty negligible.

Got it. So in other words, you're saying, I don't really care if it's 25 or 2.5. And the good news is these brand new scanners are faster, which is why they're giving you less radiation.

Exactly.

They seem to have better resolution.

And the same thing applies. That's on the diagnostic side, on the therapeutic side, where I am, our machines are called linear accelerators. And there's a similar progression as we've been able to focus the beams more and more precisely. It's a modulation of the beam, meaning you have a lot of photons being showered in the general vicinity of a patient, but you're blocking out everything except for a small area to treat. And the same way the newer machines do definitely have a lower exposure to the least in the room in general.

So what should people be thinking about in terms of extraneous radiation? When should people be saying to their doctors, hey, do I really need this? For example, when you go to the dentist every year, they typically want to do a set of X rays. Is that anything people should be worried about?

Not at all. Not in the least. I would certainly not skimp on dental X rays. Mammograms if it's someone that needs cardiac workups and things like that, the risk benefit ratio is so heavily in favor of doing these studies that I don't even think twice about them. I think part of this comes from, you know, I've been doing this 25 years now. I have so many patients, by the time they come to me as a cancer patient, they've been through so many CT scans. And nowadays we do PET scans. We follow up with annual PET scans after the factors, which are not only the ct, but you've got a radioactive isotope that's being injected into them. And we just really don't see. Now, there are certain situations where you are giving, for example, an intravenous therapeutic dose of radiation, say for thyroid cancer or things like that. There's certain new theranostics that are out there. In those situations you have to be concerned because they can get into the multiple, into a sievert range. But when you're in these millisievert ranges, it's so important to do these studies. The benefits of mammograms are so proven. Dental X rays, I don't really think twice about them.

Okay. By the way, just on the PET scan. So if you do a PET ct, for example, which again, these are not routinely done, these are typically done in oncology patients only. But just for my own understanding, are we talking 50 to 100 millisieverts? If you're doing a whole body pet.

CT, I think it can be in that range. Yes. I think that's exactly right. So PET CTs are relatively new, but up until maybe a decade ago, the PET scan was independent of the ct. They would do them separately, but the data is so much better when you have the anatomical CT data overlay with the pet. That whatever that extra dosage is, I think it's well worth it in terms of the resolution of what we're able to see and what we're able to gain from that information.

Okay, so now let's pivot from the diagnostic to the therapeutic. Is it safe to say that the majority or the most prevalent or common type of radiation oncology treatment would be for breast cancer?

Breast and prostate are the number one. And number two, depending on what patient population you're talking about, prostate may even be a little bit higher. And this goes back to the 80s when the trend from doing a Halsteadian type of radical mastectomy was falling out of favor. And the randomized data was obtained in the 80s showing that a lumpectomy, breast conservation, which is lumpectomy, Followed by radiation has the same outcomes in terms of overall survival as a full mastectomy. That's when breast really took off in the 80s. And around the same time is when prostate radiation started becoming a thing. But at the time, radical prostatectomy was obviously still king. But now in the 2000s, I think prostate has taken off and it's probably close to matching breast cancer. Now those are number one and number two. But we also do, depending on where you are in the country and what your affiliation with the hospital is, tons of CNS lung lymphoma, gi, not colon, but more rectal and anal distal GI cancers. Even in the pediatric world, we try to avoid radiating children, but it's a very big part of that as well. So we use it for almost all types of cancer now, actually all solid tumors anyway.

Well, let's talk a little bit about breast cancer, given how common it is. I'll tell you something funny. Despite training at Hopkins, I never once did a radical mastectomy. I mean, it was already long gone from clinical practice 25 years ago. And again, just for listeners, to make sure they understand the difference between a radical mastectomy and a mastectomy, or what's called now a modified radical mastectomy, the current version of a mastectomy removes all the breast tissue along with the lymphatic tissue in the axilla. Certainly I did more than my fair share of those. But the radical mastectomy, the halsteadian procedure, removed also the entire musculature of the pec, pec major, pec minor, the whole thing. It basically was a disfiguring operation, Debilitating woman with nothing but ribs. Imagine what it's like to not even have pec muscles. You sort of take for granted what you need to do to move your humerus. And yeah, to think that it's only been 40 or 50 years that someone had the courage. I think it was probably Fisher, right?

Fisher's big study in the 80s, which now we have 40 year data from that. And it's interesting how now even the modified radicals are relatively rare. We still have some advanced cases that they have to go that route, but we see tons and tons of patients now who are so much happier. Their quality of life is much better by just having a simple lumpectomy, a central node biopsy. And if it's all negative, especially if they've had their mammograms, you get a small T1 or T2 tumor, we give radiation to the whole breast following that, and the radiation is again Fractionated into small daily bits, they'll get somewhere in the neighborhood of these days. It's actually only about three weeks of treatment. Maybe about, I say 40 gray in roughly 15 fractions we used to give even when I was in a couple of decades ago, we were giving 50 to 60 gray was quite a bit higher dose, but 40 gray and 15 fractions to the full breast. And with the modern technology, we can cover the breast tissue without a significant heart or lung dose. We can even use tangential beams even if it's a left sided tumor, to stay away from the heart, which is things that we couldn't do very well in the past. The overall and disease free survivals are pretty much comparable to someone who had a modified radical.

Yeah. For folks who want to know more about that, Sid Mukherjee in I think it was in the Emperor of All Maladies has a chapter on this book.

Fantastic book and one of your best podcasts. Love that guy.

Yeah, he's a legend. So let's talk about that. So a woman has a stage one or a stage two breast cancer. Typically these days I think they're moving mostly to neoadjuvant chemo before resection.

Yes, in a more advanced case. But if It's a typical T1 or even a small T2 that we see, they may not need any neoadjuvant therapy. They just will have their lumb. If it's a, like I say, a 1 1/2 centimeter mass that's easily resectable, they'll remove that just without any neoadjuvant treatment. And we'll do adjuvant radiation and then potentially depending on the receptor status, adjuvant hormone therapy, which is the domain of the medical oncologist, but we still work with them. So just surgery followed by three to four weeks of radiation.

How long after surgery can you begin radiation wound healing?

We give them a little bit of time. We generally do our CT based simulation and three dimensional planning maybe two to three weeks after their surgery and then by the time it takes about a week to do all of our computer programming and then we'll start the treatment within three to four weeks post op.

So tell me a little bit about that. I was completely unaware of that. So I'm a woman, I've had a lumpectomy. Sentinel node was negative. So I've got an incision about this long for the listener. 5 centimeter, 6 centimeter incision. They've probably closed it with beautiful internal sutures. I've got some Steri strips. They're off in a week, and I've got a nice little scar. A week later, I come and see you. How many weeks after that?

I usually will see patients for consultation. A lot of times the breast surgeon will send them prior to anything being done. So I'll see them for their initial consultation ahead of time. But then we plan on doing what's called a planning procedure or a simulation, where we're going to put the patient on the table and essentially do a dry run for their treatment, usually a couple of weeks after treatment. And that involves essentially positioning the patients. Typically, for a breast patient, they'll be prone with their arm behind their head. We call it the movie star pose, to get the arm out of the way of the axilla, essentially. So by putting them in this position and then putting them on a wingboard, that'll slightly elevate their torso. And there's a lot of different geometry here that we can use. Back in the old days, they had all kinds of ways of doing plaster casts and things like that, but we essentially do now we'll use a, what we call a vac lock, essentially a bean bag with a vacuum port. And the patient sinks into the bag. We suck all the air out of it and lock. It becomes a rigid cast of their body. And that way they fit into the groove that we've made for them. We'll actually form it and mold it around their elbow so they're comfortable. Many times with patients who've had an axillary dissection, they may have a little bit of scarring, a little decreased range of motion to be able to get their elbow back there. So we'll work with them the best we can. Whatever position we get them in, we do a CT in that position. And that's the position we have to reproduce for the daily treatment. And the key there is that when they have their arm out of the way, we have to have room so that the machine can move around from different angles. The actual radiation machine has a gantry that can move really 360 degrees, can treat from any angle you want. But we have to be able to model tangential beams. We don't want direct anterior field that's going to radiate the breast, but the photons are going to go right into the chest. By using an angle, we can cut across the surface and actually shape the beam to match the curvature of the chest wall. So we cover the entire thickness of the breast tissue. Or even in the case of a advanced, maybe a T4 patient, something like that. We may even do this post Mastectomy. So you're treating the full chest wall and we go a little deeper below into the ribs, into maybe the first inch of lung tissue below that. But by using these tangential beams, that really minimizes the treatment, the photons damaging the lung tissue. So all of that is planned ahead of time. We do a CT scan just to be sure.

Planned pre resection because you're seeing the tumor itself.

What I meant was pre treatment.

Got it.

So post resection, you'll see a tumor bed. The lumpectomy cavity is obviously clearly visible. It's a fluid pocket on ct. So I'll scan the whole chest. Takes about a week. I have a whole team, have a wonderful staff, a radiation dosimetrist that helps do the computer planning, and then a radiation physicist that actually calibrates the machine prior to actually starting the patient. So we do the scan. Of course, the CT scan is two dimensional slices, but we have three dimensional modeling software. So I have a full 3D model of the patient. I can look at the slices or.

How thin it varies.

This is not a diagnostic scan or anything. So usually something like 2 millimeters, 3 millimeters. We don't have to go super high resolution. And so that way, once it's reconstructed, then I can have a nice idea of what angles to bring the beams in at. Because every person has a slightly different curvature to the chest wall, you're gonna have to customize the anatomy. Different breast sizes. We have all kinds of different techniques. I won't go too much into the details, but if someone is very large breasted, we could even treat them prone, have a special pillow to allow the breast to hang down.

And it's also, I'm guessing, where the tumor was in the breast. So if you have large breast and a superficial tumor, definitely prone would be amazing. The tumor bed is so far from the patient.

That's true. But our technically what we call the clinical target volume, the area that we're trying to radiate, would actually include the entirety of the breast tissue, even, oh really, all the way down to the chest wall. So there's two different ways. There's breast radiation, which is what most people get, but what you're describing actually is partial breast. We would just target the lumpectomy cavity. And that can also be done. We save that for, usually for older women who have a very small tumor. And when I say older women, it's more because of the fact that the remainder of the breast remains untreated. So a local recurrence is a little bit more likely. In someone that has not had full breast radiation, but in a selected subpopulation of small breast cancers. In someone with a very large breast, you can do partial breasts where you're only targeting the lumpectomy cavity. But for most of our patients, we actually do treat the whole breast as standard of care, plus or minus the axilla. That's where the pathology comes in. Because if they did have a positive lymph node, then we have to go after the axilla and sometimes the supraclavicular and even internal mammary nodes in some cases.

Okay, yeah. So this is infinitely more involved than I thought, which means I'm not the only one that probably was ignorant of what is involved. How long does each session take when.

They'Re actually on treatment? It's about 15 minutes, sometimes even a little bit less than that. Some of the newer machines can deliver the beam even faster. But When I say 15 minutes, I'm talking about. I have four patients an hour, typically, so in and out of the room in 15. So that includes getting them on the table. The key thing for accuracy and reproducibility is positioning. So the reason we made that mold and we've not only did we get them in position, but I've also got a couple of dots on their skin to use as reference marks to make sure that the patient is in the correct position. That whole process probably takes five minutes every day when the patient gets in the room, and then maybe another five to 10 minutes for the actual beam to be on. And my favorite thing is to come in the room after the patient's first treatment. And the most common question I get is, hey, doc, when do we start? And I'm like, no, ma'. Am. That was. They're like, really? That was it. Because the patient feels nothing. So the machine will go through its various angles. It's pre programmed. The entire process is about 15 minutes a day. And they can leave feeling the same as when they got there. Just like getting any X ray, they jump in their car and go right back to work or to the gym or the golf course.

When did this become so automated with the robotic arm and stuff? Did you do this in your residency, or were you the ones manually doing that in residency?

So I was in residency in the late 90s, early 2000s. So it was a very interesting time because we were at the cusp my first year of residency, and I was at UTMB in Galveston. It was a combined rotation with MD Anderson. So we were at a time. This is 1998. We're talking about where at the end of the old era, we didn't even use CT planning, we just had a couple of orthogonal films and we were literally drawing our tumor volumes out with a grease pencil on a physical X ray and using that cutout to go trace a styrofoam negative and make a metal or a lead alloy block, which you would slide this, basically this aperture in the path of the beam. That's the way it was done for decades. And so we were still doing that when I started residency, but by the end of residency we had full on CT planning, where now we're doing a full CT scan, doing everything virtually, and of course it's far more precise and you can model multiple different iterations. Okay, do I want a beam coming in from this angle? Do I want to bring in an orthogonal beam from here? Do I want to block out a little bit more of the chest wall to get the heart dose down? I can see all that stuff now. So by the time I finished residency, we were basically doing what we do now, albeit with much slower computers and just being in the infancy of that, it was probably more like 20 to 30 minutes per patient. But the last 15 years, roughly, to answer your question, things have been much more automated. And instead of having lead blocks that you're sliding into the path of the beam, now everything is shaped in the head of the beam by our computer. So you hit a button and when I've already programmed the treatment planning values, the machine knows how to shape the beam to match the aperture of whatever you're trying to do. So that's all fully automatic now. So the therapist job, we have a radiation therapist who actually positions the patient in the room. They get them in position, they take a picture X ray first, either a cone beam ct, which is a low dose ct, or just a PA and a lateral film. And we actually overlay that with our planning imaging to make sure that the original reference from the planning day matches today's image. The machines will actually superimpose the daily image with the reference image. So everything is automatic. I can see. Okay, are we directly on? If everything lines up correctly, then we literally have two images that look identical. I just see one image, which if it's slightly off, if there's even a few millimeters this way or that way, we account for that by moving the table. The table is motorized, so the patient will be laying there and they'll feel it move just a few millimeters this way or that way until we have perfect concordance between the daily setup and the original, that's really, really improved our accuracy. And the regional miss, the geographic miss, which was a problem in the old days when we didn't have digital imaging. And all this stuff is essentially gone now.

The actual radiation beam is generated by what the ion is generated by.

So that's another thing that has changed now, essentially, when I say now, the last, basically 30 years. Most machines in the US are linear accelerators. So these are artificially generated X rays. It's essentially accelerating electrons through a long vacuum tube, essential electron gun. And at the very end of the tube you've got a tungsten target. And so the electrons hammer that target and then they shower photons out. So you're generating the X rays that way. And this has been done. Actually, I think your alma mater, Stanford, had the very first one in the US the medical linear accelerator. Prior to that, they were using these for atom smashers. And, you know, they have the gigantic machines that we use for physics, but they started in London, I think, in 53, and then I think in the late 50s, Henry Kaplan @ Stanford had the first one. So we're essentially still doing that even today, what, 70 years later. But the key difference is how we're able to shape those photons once they come out of the machine now. And so when the actual photons are coming out, they're completely unfiltered. It comes out in a cone shape and it diverges, just as any light source would. You know how when you hold a flashlight to a wall, you get a nice precise circle. As you pull the flashlight, it diverges. So we have filters and we have what's called the multi leaf collimator that can actually shape the beam, as I mentioned earlier, that can actually match the anatomy of the patient. But now that's all done automatically. We program it ahead of time, as opposed to the old days when we had to use lead blocks that were actually physically blocking the beam. But basically the linac has been the standard. Prior to that, we were using a Cobalt 60 machine, which is essentially. It's not even a machine. It's basically just exposing a patient to a radioactive isotope and then shutting the jaws again. And actually those are still in use in most of the world. There's a few left in the US but they've mostly been decommissioned now because the linacs have taken.

Over. When you say that a typical treatment might be 15 gray over the course of the three weeks, fractionated over 15.

Treatments. So it's actually about 40 grams. 40 grams, sorry. So roughly 2.5, 2.6 gray per day. And you're right. Times 15 treatments. So you're getting roughly 40 gray to the breast. And then we usually actually do a boost. So we'll give what we call a tumor bed boost. We give a little extra dose to just the lump itself, the lumpectomy cavity itself. And there was a couple of French trials that showed that adding an extra 10 gray over an extra five days. So two gray times five just to the lumpectomy cavity itself improves local control over just whole.

Breast. Okay, that's actually what I was going to ask. I was going to ask if the 40 Gray is distributed completely uniformly across the breast. The answer is no, it.

Is. But then you have that boost, extra boost. It's a customization based on the patient's pathology. I'll occasionally have a patient that the breast surgeon will call me and say, hey, Sanjay, we did our best, but we had a persistent positive margin. I went back and did a re resection and there's still a positive margin. Or maybe the positive margin is at the chest wall. They can only go so far. In that case, instead of giving a 10 gray boost, I might give a 16 gray boost or something to account for instead of just treating microscopic disease, potentially macroscopic residual in that sort of situation. So every patient's a little different. And then the axillary nodes themselves are normally not treated in an early stage patient. But depending on the risk factors, if it's a very large tumor or if there was a positive sentinel node, maybe an incomplete axillary dissection, in many cases, we end up treating the full axilla. And in some cases, when it's advanced disease, we end up treating level two and level three. So you end up getting the super clab as.

Well. If we go back in time to 25 years ago, 30 years ago, versus today, what are the typical side effects that a woman experiences from this treatment? And by the way, was she typically getting 40 gray 25 years ago, or was that a little more? I think you said, and now they've come down a bit. It was sort of 50, 60.

Gray. This brings up a point I need to kind of emphasize. It's not so much the total dose, it's the dose per fraction. So how quickly are you getting it? So the standard of care was actually 50 gray rather than today's 40ish gray, but it would usually be given in two gray per fraction daily doses rather than the 2.6, 2.7 that we're using now. So the effective dose, when you take into account there's a whole radiobiology lecture that we're not going to bore people with. But taking into account the dose per fraction and the total dose, the biologically equivalent dose or the bed, is roughly the Same now at 39.9 gray given in 15 treatments versus the old 50.4 gray that was given in, say, 25 to 28 treatments. So it was a longer process, you're right. And we still do that in some cases. And this comes back to another question you asked about, about the homogeneity of the dose. And so our goal, of course, is to have 100% coverage of the whole breast. But the reality is the way that photons are going to be interacting from different beam angles and whatnot, you're always left with hot spots and cold spots. And so the biggest difference between what we're doing now versus the old days wasn't so much the total dose, it was the actual homogeneity that you touched on. So the heterogeneous old way of doing things with a cobalt machine or with a low energy X ray, unfortunately meant that there were hot spots and cold spots in the breast. And that, of course, could either be manifested as scar tissue if it's a hot spot, or, heaven forbid, a geographic recurrence if there was a area that was underdosed. So with the modern computer planning, we're much more homogeneous. So even though you may say, I got 50 gray back in 1995 and now I'm getting 40 gray, you are now getting 40 gray in two and a half gray fractions, which is equivalent to the old 50 plus. We don't have 150% hot spot and a 60% cold spot. We have a nice 100% match all the way across. It's like a CAD cam type of thing. I'm about as close to an engineer as an MD can be. And so we do actually simulate the dose distribution of the radiation in the tissue, in modern days, we get a nice homogeneous dose. And therefore that goes to your next question, which was, what does the patient experience? Maybe not so much 20 years ago, but more like 30, 40 years ago. With the older cobalt machines, they would get a terrible dermatitis. Many times it was moist desquamation confluently over the whole chest wall. Axillary desquamation is always bad because of the friction of the arm. But with the modern treatment now with, first of all, not using cobalt, using linear accelerators, the energy of the photons is higher, which means the skin dose is slightly lower. So you're getting maybe 100% on the skin rather than 150% like you once did. So we don't see anywhere near the skin reaction that we used to. It's more of a maybe a grade one or a grade two erythema. So mild redness or maybe sometimes a little bit of sunburn, but nothing as severe as we used to. So these days, patients do still get a sunburn. We give them a little free samples of Aquaphor or they can use an aloe vera plant if they have it. Just your normal type of skin care stuff, as opposed to the old days when we were actually treating essentially burn victims with silver sulfadiazine and heavy duty narcotics and things like that. The modern era, it's so much better that a lot of the patients, especially if it's someone that doesn't have a very large breast, there's less energy being put into a smaller sized person. They don't get anywhere near the skin reaction. And that's why if you did have a very large patient, we actually still use the old 50 gray in 25, because you're giving less dose per day. And when you do have a very large breast, where you're going to have areas that are going to have hot and cold spots, sometimes that's still needed. So we have to tailor it to the individual is, I guess, my bottom line.

There. Did anybody ever look at when you had the very disparate hot and cold spots and follow women for.

Recurrence?

Yes. Was there any association between the cold spots and.

Recurrences? There certainly is. And so the problem was, is that in the old days you didn't have computer modeling. And actually the old school physicists got to give your hats off to those guys that had slide rules and probably abacuses or whatever the heck they had back then, where you couldn't really tell exactly where the hot and cold spots were by actually having a computer show you, you had to go based on the fact you choose a photon energy and you know what the dose distribution at various depths is. And so you would try to minimize that by again, having beams coming in from different angles. And then by using multiple angles and multiple fields, you could paint in the dose as best as you could. But yes, certainly there were issues where as you get deeper into the tissue, the dose would be lower. And then this is again before my time, but there certainly were studies showing that there were geographic misses that was obviously not good, which sometimes would lead to like a salvage mastectomy or something like that. But in the modern Era, not so.

Much. What is the impact of breast implants in this type of treatment? Either saline implants or the older. Actually, they're not older now, they're back in.

Vodka. Right. The silicone, either way, the X rays we use, they are not at all affected by that because it's essentially tissue.

Equivalent. Pardon my ignorance. I completely forget. Are those implants typically under the pec or between the pec and the.

Breast? So we see.

Both. What's the current.

Standard? I think most of them we see are actually under the muscle, silicone under the pec. But I've seen them both. Even now, the plastic surgeons have different criteria for that. But regardless of what it is, if it's under the pec, then of course it's really a little farther away. It's not a huge issue, but the radiation will still affect that area. But typically these implants are pretty tolerant of that. The only issue down the road is they may have a capsular contracture or something from fibrosis. The bigger challenge we run into is for our post mastectomy patients who are going to be reconstructed and they have expanders put in. And that's where the relationship between the radiation oncologist, the surgeon and the plastic surgeon is.

Key. Explain to folks what expanders are, how that works.

Surgically. So essentially what's happening is when you have a full mastectomy, if a patient wants to have their breast reconstructed later on, the breast surgeon will remove the breast, but then the plastic surgeon will come in and place some sort of a placeholder to allow the soft tissue and the connective tissue and the skin to stretch to allow for future implant placement. And so those tissue expanders, they can actually inject saline into them with a port and gradually stretch them with time. That's normally what they would do if there was no radiation involved. Again, most mastectomy patients really don't need radiation because this gets away from what we mentioned earlier, where breast conservation is lumpectomy only. But there are some patients with a full mastectomy who are going to get reconstructed. So they come to me when I do their CT scan. They have this expander in place from the breast surgeon. So we have to again modulate the beams and we treat the entire chest while we make sure we're covering everything. But simultaneously we have to make sure that we don't have those hot spots in the area of the expander where potentially you could cause scarring and fibrosis and cause the expander to have to be removed. Have the plastic surgeon have to revise it, that becomes a whole nother hello beans there that we don't like to mess with, but we have techniques now to be able to keep the dose off of them. And again, as you mentioned earlier, whether it's silicone or saline, it's roughly the same density. But some of these tissue expanders have bits of metal in them. They may have other artifacts. And so when I'm treating with photons with X rays, depending on what you're hitting, the effect is based on the density, the atomic number of that tissue. So metal behaves very differently. Bone behaves differently from air. But when you're in the spectrum of saline, tissue, water, it's all basically the same. We can model all that. Very much like I'm getting ahead of myself, but very much like when we have a prostate patient with a prosthetic hip, a piece of metal right next door, we're able to compensate for that with the modern computer treatment planning.

Systems. Do women experience any systemic symptoms from radiation, like nausea or vomiting, or.

Is that not pretty much not at all. The only time we see radiation patients who have nausea or vomiting, it's a lot of times for other sites, they may get concurrent chemo radiation, where the chemo could be responsible. But for breasts, we don't do concurrent. It's usually sequential. The only time I really see radiation induced nausea, if I'm treating an esophagus or a pancreas or something that's treating in the abdomen or somewhere along the GI tract, where nausea is more of an issue, typically not for.

Breast. Okay, let's talk about prostate, which is obviously also the bread and butter of the field. So first off, which patients are typically being.

Radiated? The answer to that has been evolving. There was a time as recently as probably 20 years ago where we only treated patients who were probably medically inoperable, that the urologist would say, hey, you know, this is a high risk anesthesia patient. Let's send them to Dr. Mehta for radiation. And that's a big reason why a lot of the older data was not as good for radiation because of the patient selection criteria. But in the modern era, as we've gotten more and more precise and our side effects have gone down and our cure rates have gone up, now it's pretty much wide open where pretty much anybody who's eligible for surgery would also be eligible for radiation. So there's not that big of a divergence as there once.

Was. You've gotten to know Ted Schaefer, who's not only been a Great podcast, but is equally, let's just say, interested in.

Cars. He sure.

Is. So you, me and Ted have a lovely little text thread about.

Cars. He and I may have another text thread in case our teams meet in the playoffs as well. He's a big Ravens fan and I'm from Houston, so I'm hoping we get.

There. Let's talk about a patient that comes in to see Ted for a biopsy. They've got a Gleason 3. 4 and then another patient who's a Gleason 44 or 45 or something like that. How does that patient navigate their way through the system as to whether or not they need radiation or should they undergo surgery? And does androgen deprivation therapy necessarily come with radiation? Or is there a scenario where you undergo radiation but you don't require androgen.

Deprivation? So, to answer your last question first, androgen deprivation for high risk disease is certainly standard of care. Gleason 8 or higher, for sure. The Gleason 7s are always a gray zone. And so a 4 plus 3 with high volume disease typically also do get concurrent and adjuvant androgen suppression along with radiation. But one of the things that's really changing now is I know Ted talked a lot about this with the decipher score where they can look at the chromosomes of the actual cancer cells and have a much more granular view of. Exactly. Are they truly high risk? Or can you say that this one three plus four is more like a three plus three? So for a lot of the three plus fours now with the decipher, and there's also an AI test. I knew you had a really interesting discussion with your AI expert that wasn't too long ago called Artera. And we're using that. That's actually in the NCCN guidelines now. So that Artera test can help us differentiate between a unfavorable and a favorable intermediate risk patient. I treated my own father not too long ago. He was the first person I did this on. The Artera test is essentially they just use the actual images of the H and E slides that were already done for the pathologist. And it's interpreted by a machine learning computer that has been trained on hundreds of thousands of prostate images from the old RTOG studies, the 94s, all the stuff that was done back in the 90s. And it can now come back and say, okay, very much like decipher, it can say that this is a three plus four, but it's a favorable or an unfavorable person in that subgroup. And so because of that, we can stratify better and actually tailor it to where maybe a 3 plus 4 doesn't need androgen ablation at all, and Maybe even some 4 plus 3s if they come back low enough on the scale. You always have to talk about the side effects and whatnot, but the standard of care was always to give concurrent androgen ablation for intermediate risk. But now we're able to really take some of those people out of the equation with these new studies and.

Is the main selling point, because most patients just want things taken out. I have cancer. Take it out is the reason that a person might select radiation therapy, especially if it comes with androgen deprivation therapy, because of the sexual function and urinary function. Like what's the main.

Advantage? Those are number one and number two. Yeah, lack of incontinence and lack of impotence. But of course, when you have androgen ablation, that clouds things a little bit. But typically the number one thing we see is patients who don't want to deal with diapers. And for the most part, although incontinence is still described to some degree in the literature, in my personal experience, I don't think I've seen a single patient who came in continent who left with anything less than that. There's no pads, there's no nothing. And then, of course, as I talked about with breast cancer, we can also focus very precisely on the prostate itself. So the dose to the penile bulb, the dose to the rectum, the dose to the bladder, are so low now that the side effect profile is essentially zero from a radiation standpoint. Now, they may be having hot flashes from the androgen deprivation and decreased libido and fatigue, as you know. But on the radiation side, because we have all these tricks now, very much like with breast, the way we can avoid the heart and the lungs. In the case of the prostate, we can almost completely avoid the bladder and the rectum and even the penile bulb now. So the quality of life, those are the reasons why people tend to choose.

Radiation. And I know we've talked about this before, you're just not seeing the.

Proctatitis. Yes, almost none. In fact, I think Ted had mentioned in his last talk, there's a gel spacer that is often inserted. It's an injection that's done transperineally, and it separates the rectum from the bladder. But in my years of doing this, when you're very diligent about how you do this, very much like a surgeon pays attention to the details. So do we? I can actually trim the dose off of the posterior prostate and just make sure the dose fall off between the posterior prostate and the anterior rectal wall is so rapid that the anterior rectal wall is always going to get some dose, but usually it's not clinically significant. And what we do to manifest to make sure that that is a daily thing, because we're talking about treating patients for multiple weeks, we actually coach the patient to come in with a full bladder and an empty bowel. And by being diligent about that and imaging daily to double check that, in fact the bowel is empty and the bladder is full, that allows those two organs to separate from the prostate. And even a few millimeters of separation is all we need to take advantage of our modern focused radiation.

Beams. And does the patient need to be coached to time their breath or anything as the beam is at that most delicate edge of the.

Rectum? Not so much for pelvic patients, but we do that for breast cancer, especially left sided breasts. So just to go back to that, you actually have a deep breath hold which will get the chest wall away from the heart. So we do that in the case of thoracic tumors. But in the pelvis, the diaphragmatic position doesn't really make any difference. It's more about bladder and rectal filling and emptying, respectively. That's much more.

Important. Everybody I've talked to who's had Lasik eye surgery always says they're so worried that they're going to do something, they're going to flinch. And do patients feel the same way when they're undergoing radiation? Like, what if I just flinch my pelvis or do something like that, it's going to get too.

Close. I get that question all the time. And from a las standpoint, I think I would be worried about. That's probably why I'm still wearing these Coke bottles, unfortunately. But in the case of prostate cancer, first of all, the dose is given over the course of several minutes, and then each of those fractions is again talking about one fraction out of multiple weeks. So even if someone absolutely had a coughing fit or something like that, first of all, we're watching them. We can stop the beam, we can stop it at any given moment. But slight variations day to day, the biggest variations are going to be based on bladder and rectal filling. We take that into account when we're doing the treatment planning. So there should really be no adverse outcome. Because what I actually do is I'll map out where the volume of the prostate is, and we will actually purposely expand that volume and treat the full dose of radiation even a few millimeters outside of the prostate to make sure that there is any internal organ motion or anything like that, that we take that into account. But typically if someone's coughing or something like that, we'll just hit the pause button and get them reset and ultimately it's not an.

Issue. What about patients that are inoperable? First of all, what leads to a patient being inoperable and how do they show.

Up? Typically, the urologists have already screened the patient. Everyone's first exposure is going to be to what the urologist tells them. And luckily, in this day and age, I'm lucky. We have people much like Ted, who are very open and who are very open to not just doing surgery, but who actually look at the other options and present everything to the patient. But typically, a patient who maybe was medically inoperable will certainly come to me. But even somebody who maybe is on the borderline, who wants to see both sides of the token, a general urologist will send them to a surgical specialist and to me, and we'll go through all the pros and cons of everything and really what it comes down to, to not belabor the point, it comes down to two things. You want to be cured, cure rate is key, but quality of life is equally important, if not more important, for most people. And so now that cure rates with our modern focused radiation allow it to get such a high dose into the prostate, we can say that they're essentially equivalent to surgery. So we don't have that deficit like we did 20 years ago when our fields weren't as precise. It was sort of the shotgun approach versus our sniper approach. Now, because the cure rates are better, then it really comes down to the quality of life changes. And that's where there's a spectrum of.

Things. Now, is this an apples to apples comparison? Because the patient who undergoes the robotic prostatectomy today does not go on androgen deprivation therapy. They get to walk around. In fact, you've probably heard Ted on the podcast, he says, we'll give those patients TRT if they're hypogonadal. Why does the patient, after radiation therapy still need to be androgen deprived if in theory, the radiation is as effective as the.

Surgery? That comes to a key point where it's trading one thing for another. You don't have the incontinence, you don't have the at least the short term risk of impotence like there is from surgery. You don't have the penile shortening or whatever other sort of things that they have to deal with it. But you have to deal with hot flashes and decreased libido and whatnot. But again, most of the patients who are intermediate or high intermediate risk are going to, if they end up not having a negative margin or a seminal vesicle invasion after prostatectomy, they're still going to come to me for radiation anyway and they're still going to need to be on androgen ablation. So there's a significant number. Now these days we'd certainly treat a lot less Gleason 6 than we used to. We observe most of them. But there's a lot of Gleason 6 folks that even in this day and age will choose to have radiation just because it's maybe a little bit more aggressive form of watchful waiting. And in that case there is no androgen ablation and they just glide through the whole.

Process. Has there been a trial of Gleason 33 watchful waiting vs XRT, no.

Ablation? No, unfortunately there's no actual trial. There's just observational studies. That's kind of what we're dealing with.

There. Oh gosh. And obviously you can't figure out what the biases are. But what do those observational studies.

Show? People don't die from Gleason 6 disease, as we all know, because quality of life, they do so well with the radiation, there is just less of a chance of it progressing to a seven. And when they come to me, it's interesting the different patient populations. I also get people, this is not mainstream, but I get a lot of transplant candidates who need a renal transplant and they cannot get their transplant unless they're cancer free. Even if it's one core of a Gleason 6, they're ineligible for their transplant. So those guys I will certainly treat. But I've been following them now for what, 20 plus years that we've been doing it. Quality of life, they do so well. And this way they don't have to worry about androgen ablation when they do become a Gleason.

7. So it's really interesting. There would be a very interesting and elegant study taking, let's call it medium to high risk three plus threes. So people based on family history or some other phenomenon, genetic or otherwise, you randomize them to watchful waiting versus radiate them without androgen deprivation. I mean, you'd have to do this as a very long term study. So the question is, outcome number one could be conversion to three plus seven requiring surgery and or androgen deprivation therapy. And then of course outcome two, the very long term outcome would be overall.

Survival. That's the key. That's why these haven't been done. You would need decades to do a.

Trial. Yeah, it's a 20 year study.

But it certainly would be interesting to see what it would show. But the real world observational studies show that all the Gleason six guys, like I would say until maybe a decade ago, we did a lot of Gleason 6 patients, they mostly were sent for.

Radiation. Why were they.

Sent? I guess it's a combination of different things. People have different levels of tolerance for watchful waiting. In the pre MRI days everyone had to have an annual biopsy and that alone is more anxiety invoking than really the radiation is. Not to mention we'd see a fair number of folks with urosepsis and you know, complications from that. So now in the MRI era we don't really see that anymore. But that was done very routinely. And because the patients had so little proctitis and cystitis, especially in a Gleason 6 where not only am I not worried about pelvic lymph nodes, I'm not even really worried about the seminal vesicles. So my field is very small, which really minimizes the side effects because the bladder, a full bladder, when it's actually full, it'll move superiorly and anteriorly where the dose is close to zero. So most of these patients, they just kind of laugh and say I'm coming from my daily treatment and I'm right back to my normal life again. In the absence of androgen deprivation, radiation has become very simple for prostate patients.

Now. And again, what fraction of Gleason Sevens can do radiation without requiring androgen deprivation.

Therapy? That answer would have been zero probably five years ago, even as recently. But now with Artera and Decipher it's probably, I'd say a quarter of them don't need it if it's a 3, 4 with a low decipher, low Artera score. And again, this is still an evolving area where I don't think anyone has the exact answer, but that's what most people are doing nowadays. And even some 4 plus 3s that have load deciphers are potentially candidates to avoid that. And the biggest change in this has now been our ability to do PSMA PET scans to follow up because otherwise I think that the extra androgen deprivation was more of a bandaid for not being able to see what's going on afterwards. Now if someone has a recurrence and you do a PSMA.

Pet.

Pet. I've got a guy that had treatment 20 years ago with radiation. Now he's rising PSA, otherwise he'd just be stuck with ADT for years. Now I see a positive paraortic lymph node on a PSMA pet. I can just treat that area and very successfully. There's no long term data yet, but it seems to be working really well. Similarly to how we would use a FDG PET to target a lung tumor in the.

Past. What about these patients that show up with two spine mets? How effective is radiation there? Given that that's a favorite spot for a prostate.

To. You're talking about initial presentation with all metastatic.

Disease? No, let's say, okay, we could talk about that or we could talk about post treatment three years.

Later. So post treatment three years later, palliative radiation does work very, very well. It would be probably five treatments. You can even do what they call sbrt, which is stereotactic body radiation, maybe in a single fraction. And it definitely is very good at. We kind of joke about it and just kind of spot weld that spot. It's not going to prevent something else from popping up elsewhere. But that's extremely well tolerated and usually it'll stop the progression at that site. So there are people who had high risk disease and to get back to what I mentioned earlier, if they had a couple of spots like that at the time of initial diagnosis. Now it's been shown that you can treat the oligometastatic disease if it's in the bone, only at the same time as the primary lesion. And the outcomes are actually not significantly worse if it's just limited.

Disease. And what is a more favorable presentation? Oligometastatic to bone or oligometastatic to paraortic.

Bone? For sure. Actually, I had a guy walk into my office with a PSA of 1900. He looked just as good as you or me. I actually took him on a TV show I did many years ago. It was kind of an interesting story. 1938, 65 year old guy, Mr. Macho had never been to a doctor in his life. Widower who decided that he was dating a younger woman now. And she's like, if you want to be with me, you got to go get checked out. Colonoscopy clear. Blood work? All clear. Oh, by the way, Your PSA.

Is 1900, which means the lab made a mistake. I mean that's what you would.

Think. Yes, that's what you would think, except for his bone scan looked like a Christmas tree. And this was in the pre pet era. I mean he had disease in every bone in his body with zero symptoms. So this is an outlier situation. But in that situation you need lifelong androgen deprivation and chemotherapy. Back then it was mostly taxol based therapy. We didn't have all the second generation androgen ablation drugs that we do now, like Enzalutamide. But at that time, when we saw that, you know, he went and got chemo and got androgen ablation. When he came back to see me fully functional guy, perfect shape, his PSA was down to 1.5 with just the systemic therapy. And at that time the tumor board we presented him, the decision was made to go ahead and treat his prostate as though he was a de novo presentation because all the bone disease had resolved. He did.

Great. So you treated his prostate and how long did he.

Live? He's still alive. This has been, I got an email from him just about a year ago. So I think he, at least as of a year ago, he was 12 years out, still doing great with zero side effects. He's on androgen ablation for life, so he's certainly gonna have issues from that. But overall still very.

Functional. How is this possible? What's the biology of that tumor that allows him to still be.

Alive? I don't think it's even necessarily just prostate. I've even seen it in breast cancer patients in the small subset where it's bone only disease with no visceral metastases. Some folks can live for a very long time with bone only disease. And I'm not sure what the answer to that.

Is. And has he suffered any debilitating.

Fractures? You would expect that at this point, but no, not even.

One. This guy's in his late 70s.

Now. He's in his. Yeah, late 70s. And has not fractured a thing and is still active. The guy plays.

Golf. I hope he still has that young.

Girlfriend. I'm not sure about that. But other than that, other than the hormonal aspects of it, yeah, it's amazing. I've seen many, many people with four digit PSAs that we get them down at least Ned, for some window of time, even if it's not that.

Long. Four digit.

PSAs? Yeah, I think the highest I've seen is 7,500. That was a person that ended up passing away. But the guy who was 1900, I think a lot of it is a function of. Just like any other type of tumor, he had all the other Risk factors that lined up. He was young, healthy, no other comorbidities.

Active. Ted has told me about some of the most terrifying cases are the exact.

Opposite. These guys that show up with a low.

PSA. With a very low PSA. A PSA of.

1.9. Those are.

Worse. Rampant metastatic.

Disease. Right, right, right. And that's the thing. You get some of these really poorly differentiated cancers that no longer resemble their prostate progenitor cells. They're very hard to monitor, and a lot of them even don't even show up on a PSMA PET.

Scan. Yeah. Anything else you want to talk about on the oncology side of this? As far as what should people know as they're engaging with a radiation oncologist? What questions should they be asking? It sounds like it's no different than surgery, where there's clearly a difference between good surgeons and not so great surgeons. There presumably are people that take the kind of care you take and agonize over the details. How can somebody find out if their radiation oncologist is practicing in your.

Philosophy? It's difficult in terms of actual metrics, even for the surgeons like, you know, Ted is excellent outcomes. But it's not like it's a published.

Series. And not only that, the best surgeons often are treating the hardest.

Cases. So it's a handicap.

Right? It's a handicap.

Right. There really comes down to finding someone who's got the experience. And in my case, because we do so much prostate, I think I've done something close to in the modern era, 7,000 cases, probably 10,000 when you include the pre image guided radiation days. Someone who specializes in the area that the cancer is located in. So someone like me, I may be extremely experienced in breast and prostate, but maybe for a pediatric malignancy, you're not going to come to me. You're going to go somewhere else or a CNS or something. That's unusual. You have to find the right tool for the job, but you have to just interview your doctor. I don't think there's anything specific.

To radiation and asking about.

Complications. I think being very open with them, saying, yeah, exactly. And so ideally, maybe you come to someone who knows something. Like, I get a lot of patients who aren't familiar with the field, but they'll have a patient, they'll have a family member that's a nurse or a dentist or a veterinarian or whatever it is, someone that has some medical background. They can say, okay, let me ask them more specific questions. And these days with the Internet, you can do all kinds of research in terms of when I'm talking about matching my volume of the dose distribution to exactly conform to the tumor volume, that's something that's very easy to talk about. But I mean, for an educated patient, they can ask to see the actual computer simulation. So a lot of my engineering.

Patients, I was just about to say engineers probably have an easier time than they.

Do. They do. And my engineering patients are really the only ones who do this. I usually pull out all the graphs, I show them dose volume histograms with area under the curve for each organ. And you can see, okay, the prostate dose area under the curve is huge. The dose of the bladder and the rectum is super low. You can actually quantify that. But for a lay patient, it's hard. Hard. It's not that easy to do that. I think a lot of it, you have to go with your gut too, in terms of this guy's had a lot of experience. And the initial consultation is where it all comes down. I'll spend an hour with a patient and go through every little nuance of what could and couldn't happen. And my main MO is to sort of over prepare them and have them be pleasantly surprised. Maybe when the side effects aren't as bad rather than the other way around. It's hard to find the right person. But there's a lot of good doctors out.

There. So let's spend a minute just on the brain because I guess that's sort of a unique case. I know it's not where you.

Are. Still do a lot of it. Oh, you do? Not as much as probably prostate and breast, but yeah, both primary and.

Metastatic. Yeah. So again, because the brain is such a sink for Mets A, it's a source of a lot of primaries, but it's also where a lot of cancer spreads. It's often a place where you can't operate either because the tumor, the met, or the primary is too close to, say, the brain stem or something too vital. So radiation is a pretty common tool there. So talk about the history of radiation in the brain and the spectrum of everything from whole brain radiation to gamma knife and stereotactic and all sorts of things in.

Between. Sure thing. The main differentiating factor for brain patients is whether it's primary or metastatic disease. And although primary brain tumors are relatively common, they are dwarfed by metastatic disease. So the vast majority of what most radiation oncologists see when you're treating CNS is going to be usually lung, especially small cell based brain metastatic disease. And so in those situations, the trend used to be where everyone would get whole brain radiation, but now with the advent of stereotactic radiosurgery, which is more focused, precise radiation, the newer data shows that you can actually just treat the area of metastatic disease as a delineated on an MRI scan and not necessarily radiate the whole brain like we used to. But for decades, everyone got whole brain radiation, and for the most part, they did all right. But the problem was you're looking at a patient population that maybe doesn't have that much of a life expectancy. Now that systemic therapy, immunotherapy, everything has gotten better, especially in the case of lung patients. They're living longer. We have evolved where we've been finding people that were previously radiated to the brain were having cognitive issues years down the road. Not for the short term, they would tolerate it well, but maybe they'd start to have more forgetfulness, an inability to remember numbers and names and.

Whatnot. And this was from whole brain.

Radiation. Whole brain.

Radiation. And give me some.

Doses. So we're talking about 30 gray to the whole brain, given in 10 fractions of 3 gray each. 3 gray times 10 was a sort of a standard.

Thing. This is a staggering amount of.

Radiation, and that's to the brain. So it's a different.

Story. Just to be clear, do you need to use way more radiation because that's what you're delivering to the brain. Is this an example of where the sieverts and the gray are very different because you have to get through the.

Skull? No. So the only difference between sieverts and gray in any patient is going to be whether we're talking about dose in tissue or coming out of the machine. Basically the dose in air versus dose in the patient. The biggest thing with brain tumors, yes, the bone certainly is going to attenuate more dose. But what I'm talking about is actually 30 gray into the brain itself. The actual brain tissue.

Issue. Doesn't that mean you need much more than 30 gray coming out of.

The machine a little bit.

More? The bone doesn't do.

That. It's not like they're wearing a football helmet or something. Yeah, photons can still pretty much go through everything. It's not metal, so it'll still go through. The dose is a little higher. And it gets to be like, for example, in a lung patient, it's more of an issue when you have multiple different areas. You got bone, soft tissue, and air. In that situation, you have to modulate the dose more. But in the case of a whole brain, it's been found, of course, that the hippocampal dose is very much related to their cognitive deficits down the road. So now that we have imrt, which is a term I hadn't mentioned before, but that's basically intensity modulated radiation therapy, which is also the magic behind allowing us to treat a prostate without burning the bladder and the rectum. And the newest form of IMRT is called Image Guided Radiation Therapy. So you hear IGRT, basically those two terms go together. But by using IMRT, it's kind of like an HDTV versus this 1960s black and white blurry set where we can trace treat with multiple small pixels and high definition, so to speak. So now when we do a whole brain, if I have to do a whole brain for multiple metastases, by using imrt, I can literally carve the dose out. I can map out the hippocampus and carve the dose out of there. So you see these two cold spots on the hippocampi and really have a very low dose there while still treating the remainder of the brain.

Parenchyma. Are there other parts of the brain that you carve out and.

Protect? That's the main one. Of course, we are going to not necessarily completely carve out, because when you have multiple metastases, really the whole intracranial space is at risk. You have to cover everything, everything. So, believe it or not, 30 gray sounds high to you, which it is, but for a glioblastoma, we use 60 gray. Granted, that's not to the whole brain. That'll be to the either. If it's an unresectable patient, it'll be the primary mass, and then we will give maybe 46 gray to the peritumoral edema. But then the rest of the brain is getting much less, hopefully zero in many.

Cases. Do we know what the survival difference is for an unresectable glioblastoma with and without.

Radiation? It's certainly worse. There's again, multiple confounding factors there because someone who's unresectable probably has other negative issues as well. If they have poor overall performance status, they have neurologic deficits. Whatever the reason, the surgeon can't operate. That makes it worse. But yes, even then in that situation, you get probably again, you're measuring survival in weeks to months, but it's probably double with radiation than without. A lot of our GBMs, though, are resected, hopefully fully resected, in terms of at least radiographic the post op MRI not showing any enhancement. If you have someone that's got a fully resected primary who's a younger patient with not a lot of neurological deficit, they can live a couple of years.

Actually. Why is this cancer.

Unsurvivable? That's the key question. I know you and I are both Rush fans. Neil Peart was lost to GBM as well. And it's so many people that's taken away. But I think it just has to do with the invasiveness of the fingers, of the tissue in terms of even when you think you've gotten the whole thing, there's microscopic fingers that are always on the periphery. And you can't just radiate it indiscriminately like you can other parts of the body, because you got the brain there. There's always a fine line you're walking between causing, say, for example, necrosis of the brain versus letting the tumor recur. And so that's really the number one issue. We do have a new tool now as far as radiation oncologists in terms of treating CNS tumors, which is called proton therapy that you've probably heard about. There's several centers in the country now, Maryland. Henderson, where I am in Houston, has a huge one. But with protons, you potentially can have the dose go into the brain to a certain depth and not exit out the other way like an X ray would. X rays are like light, it goes right through you. You may have a decreasing dose, but it's kind of like a bullet. You got an exit wound going out. With proton therapy, this is one of the areas where protons shine because you can actually modulate what's called the Bragg peak of the physics of the protons to where it'll go a certain depth and not go out the other way. So down the road, hopefully we'll start to see improved survival. Well, so far it really hasn't shown to be a huge improvement, but there's less integral dose to the rest of the brain. And especially important in pediatric patients where you've got children with growing skull bones and if you can avoid radiating the growing bone to cause a deformity later on, that's huge. So proton therapy is one tool we have. But I wish I had an answer for GBMs. That's going to be a game changer whenever that does.

Happen. I find GBMS to be just such a frightening type of cancer, and I do wonder if, if it's going to require some sort of injectable immunotherapy or something. I think so. I just. Yeah, you have to basically figure out a way to treat the brain systemically. You have to mechanically overcome the blood brain barrier and come up with some sort of systemic treatment for it. Okay, so today, how many patients are undergoing whole brain.

Radiation? Whole brain radiation is probably to give you a number. I don't know what the absolute number is, but it's probably 10% of what it was 20, 30 years ago. The original studies out of Kentucky that Patchel had done in neurosurgery, everyone used to get whole brain radiation following resection of the metastasis or even if it was unresectable. And there was some good data back then supporting that. But nowadays, rather than whole brain, you're usually going to do a focused treatment just to a smaller area. And this is kind of a universal trend to less radiation dose to a smaller volume. Same thing in lymphoma. You want to treat just the enlarged lymph node and not the entire higher lymphatic axis. So it's the same idea where you're trying to minimize side effects. So whole brain, we still use it in specific cases like for example, small cell lung cancer. Part of their regimen is going to be once the primary has been treated, if they have a complete response in the thorax, prophylactic cranial radiation only for small cell PCI 20 gray 5 fractions been done forever shows an advantage they have.

Lower. How much of a reduction in CNS.

Met? It's a lot. I think it's probably 70, 80% reduction in CNS failures because they all fail there. Otherwise small cell, they just all do that. And at 20 gray they really don't have too many side effects. But again, of course the caveat is always extensive. Stage small cell lung patient isn't going to have a long term survival, but at least they won't fail in the brain. It's a quality of life.

Issue. I'm sorry, this is done with every small cell patient, no matter how early it's.

Caught. If they have a complete response to primary treatment. Yes, basically everybody. Maybe there's some nuances, but for the most part.

Part. Okay, so what's a gamma.

Knife? So gamma knife is instead of using a linear accelerator, it's actually using cobalt 60 like I described earlier. But you have multiple small sources that can actually be used. Very high resolution cobalt essentially. So you're doing the same thing, but instead of using a linear accelerator based treatment, it's using.

Cobalt. So is that used.

Anymore? There still are centers that use it. It still works very well for what it is, but the focus is very narrow. There's a lot of children's hospitals and all that. I think we're still using using it, but the linear accelerator, which is abbreviated linac, the LINAC based stereotactic radiosurgery for the most part has taken over from that because it can do all the same things and also have more flexibility to do more than just CNS. St. Jude's Hospital has a fantastic PDCNS program and they still have. Well, it's been a while now, but they did have a gamma knife last time I.

Checked. Okay, so we've talked a lot about radiation. We've touched a little bit on the idea of radiophobia, but. But maybe let's use that as a bridge to talking about using radiation to enhance tissue as opposed to eradicate a subset of tissue. Does it stem from nuclear accidents? Is that largely where radiophobia comes.

From? I've done a deep dive into this this year, which goes along with all these benign cases that I'm treating now. They're essentially arthritis tendinitis, which we'll talk about. And what's really interesting is that, that this radiophobia is largely a US based phenomenon because the first cases, first of all X rays were discovered in 1895 by Roentgen. In 1898 there was the first case described of actually radiating both arthritis type things or ankylosing spondylitis or other arthritides and also tumors. Even back then we had no idea how it worked. But there were cases pre1900 that were already being used for that. That and then in the subsequent now 120 plus years we have this divergence where Germany and the UK, all of Europe really are using radiation routinely for arthritis and tendonitis. But in the US it seems to be a basic nuclear phobia, the Cold War, like you mentioned. But another thing that's been talked about, there's a guy named Jason Bechta that has a really good podcast on the subject. He's out of Vermont. Standard Oil, the Rockefellers and all, actually had a massive lobby group that were actually actively promoting oil over nuclear power plants. The amount of spread went from just the energy industry into the just the general zeitgeist of the entire country. And so at that time the radiophobia just caught on. And it was of course bolstered by World War II and seeing what happened in Hiroshima, Nagasaki. And then on top of that, you've probably heard about the radium dial workers. There was a movie that's actually called the radium girls. These are essentially women in the 1920s that were using radioluminescent phosphorus paint to paint the.

Watches. Watch dials.

Yeah. Being a watch guy, you'll probably appreciate that. But that was the only source of illumination they had. So in order to keep the brushes very fine, they were literally dipping it in the radium paint. And then after each brush, they were licking the brush to keep the tip real fine. And so they were ingesting bits of radium. So there were a number of cases where they ended up. The radium is metabolized like calcium, so it was actually incorporating into the mandible. And they were getting osteoradionecrosis of the jaw and things like that. So all of these different phenomena added together became a big deal, because prior to that, people were using radiation for all kinds of crazy things. It was in suntan lotions and waters, and there was something called vigoradine that they were using for ED that you could topical salves that had radiation in them. It was literally no end to it. And then when all this sequela started to come out that, hey, maybe this isn't such a good idea idea, that's when things took off. But now that we look back, the reality of it is, is that a lot of that was really overblown. Even so much so that those radium dial painters, which we hear about this from day one in our residency training, there was only a small percentage, like I think 50 out of 1500 roughly, that actually had toxic sequelae. So most of them.

Didn'T. Is there a way to quantify how much exposure they had.

To. And that's the thing. You know, they may have looked different ways, but there have been some basic ideas. It was, again, we're talking about at that era was probably a couple of millisieverts to that particular area, but it was daily for decades. And so part of the reason why, if you actually look at the numbers, it was probably a super high exposure. But when you spread that out over such a long period of time, that's sort of the general trend. Like I mentioned earlier, it's not just the dose, it's the dose over time. The denominator matters a lot. And so that's why most of them actually did very well. They even used to use radium internal nasal applications in the 19, I guess, 1920s to 1940s, essentially a radiation equivalent of a tonsillectomy or adenoidectomy. And it was done in something like a half million to 2 million children in the US and even in the armed forces. It was done routinely back then and there's been very few adverse sequelae that were reported. I don't even know what the dose was, but it was high. So there's a lot of cases where the exposure, Based on our 50 millisievert rule we talked about would just make people fall out of their chair. The actual reality of it is that many times the actual end results aren't as bad as we had.

Expected. Affected again, hearing you say this, Sanjay, the listeners are going to be thinking.

What?

Yes. Because we're all so brainwashed into believing that radiation is.

Horrible. Right, Right. I can tell you so many stories. You know, I got patients who have had to treat. I had actually had a guy who was involved in nuclear testing at Los alamos in the 1940s. He's passed away now, but I saw him in his 80s. So this was in the early 2000s. This was 60 years after that. They had very little monitoring back then, but he was close enough to feel the heat from a thermonuclear bomb. And by the time I saw him, he had had thyroid cancer, as you would expect. He'd had one or two lymphomas. I think I ended up treating his prostate. So he'd had at least four or five different malignancies, but the guy was as functional as most 80 year olds are. The guy was still walking and talking and doing just fine. And it actually seems that when you look at the population studies that were done outside the blast at Hiroshima and Nagasaki, when of course, the initial concentration, everyone dies from the thermonuclear energy energy. But as you get several miles out, not only are the cancer rates actually roughly the same as the background, you actually see, again, evidence of hormesis where you have some patients in whom, or maybe not hormesis, but some sort of radio protection where you actually have lower rates of leukemia and thyroid cancer when you get a few miles farther out than you did in the general population. So it's all very much dose dependent, time dependent. But I think the human body, we're evolved really to handle this to a larger degree than we realize because again, again, mammalian DNA, we came from the background of the animal kingdom where there was tons of exposure from natural cosmic rays and whatnot, and our predecessors had to be able to survive. Our DNA had to be somewhat resilient in order to get to this point. I think it's more resilient than a lot of people give it credit.

For. So this first came up maybe a year or two ago when I was lamenting. It must have been two years ago, I guess, because I was kind of lamenting my Achilles tendon, which I wouldn't say it was injured. I just had a little bit of tendonitis. It was just bugging me a little.

Bit. You and me both.

Brother. And so it was through that discussion that we got into what we're talking about now, which seemed crazy. I just decided I didn't feel like driving to Houston all the time to undergo therapy. And my Achilles is fine now. I just did sort of standard therapy. But I've sent a few patients to you who have had similar injuries. Both high hamstring tendinopathies, Achilles tendinopathies. So talk a little bit about this idea. How prevalent is this type of treatment in Europe? How prevalent is it.

Here? So prior to probably 1970 or maybe 1980, it was very prevalent, even in the US it was very widely done. Everyone I talk to them about it now, it sounds like I'm doing something experimental and radical. But if you go over to Germany again, going back to ankylosing spondylitis papers in 1898, they do something like I hear, between 20 and 50,000 patients a year in Germany. Germany, it's mostly observational studies. There's very few randomized trials. But low dose radiation for tendonitis, osteoarthritis, plantar fasciitis, all the ities you can think of, bursitis. A low dose of radiation has a similar anti inflammatory effect to what you would get from a.

Cortisone. And let's define the.

Dose. So now we're talking about very low dose, meaning 50 centigray or 50 rads given six times over two weeks. So 3 gray 0.5 times 6 is 3 gray to the affected joint using a very low energy machine. So this is especially in the case of someone who's got a hand, you're talking about electron beam.

Radiation. Sorry, let me just make sure I got that straight. You were giving 40 gray total to a breast. A breast. And now for the Achilles, you're giving how.

Much? Three gray, six fractions of half a gray each. So all six fractions combined is about the dose of one fraction from for a typical cancer. That'll give you the idea and giving it in a superficial fashion where, especially if it's a hand, you only have a couple centimeters of thickness. So we use what's called electron beam therapy, the same linear accelerator when the electrons go and hit the tungsten target and make photons. If you remove the tungsten target, you just get direct electrons and electron energy can be modulated to where you can treat a superficial skin cancer. You can treat a knuckle, I can treat a temple squamous cell and not go into the brain. In the old days before they had linear accelerators, I told you, this goes back to the turn of the previous century, they had orthovoltage machines and these basically created kilovoltage X rays, not the mega voltage X rays we use now. And all they could do was superficial stuff back then. And that's where it works very well. The dosage has changed tremendously. But these days the biggest data comes out of Germany. Half a gray, three times a week, Monday, Wednesday, Friday, for two weeks, just to the affected joint. And it has an anti inflammatory effect very similar to either a cortisone shot or an.

Nsaid. How many weeks is the.

Course? Two weeks, Monday, Wednesday, Friday, six treatments. And the protocol is what we typically follow. The German protocol is to wait 12 weeks and you usually see depending on the joint, somewhere between a 60 and 80% success rate where the pain is, if not zero, at least markedly decreased. And then after 12 weeks the German protocol allows for a retreatment. And then that point you get up to 90 plus percent success in terms of.

Reducing. And this is for joint.

Arthritis. Arthritis, tendinitis, bursitis, plantar fasciitis is a really big one. Now that we're doing a bunch of. I've done probably close to 70 cases across the board, which is kind.

Of remarkable because anybody who's had it, you know, I had it once back in med school exactly 25 years.

Ago. Did you get it treated or.

Was it just went to PT and rolled on golf balls and did the usual thing, but it took, took months to get.

Better. It's such a big.

Deal. So you're saying of the patients that are coming to see you with plantar fasciitis, how many of these patients, how long have they been.

Hurting? First of all, many times for years. In fact, my biggest cohort recently, which is still relatively new, I haven't done thousands of patients. Like, I can speak from decades of experience with cancer. We're talking about dozens to hundreds. A couple of surgeons that were having trouble standing and operating, they literally couldn't perform their normal duties. Six treatments to the fascia and they're walking like nothing ever.

Happened. How long after the last treatment did it.

Take? In the case of plantar fasciitis it was almost immediate, within a Week. I have other cases, especially when we do like knee arthritis, if there's a lot more pathology going on in a knee. I treated my own Achilles, which I can tell you about. Took two months or so. I was almost wondering if it was going to work or not. I was my own first patient before I offered to anybody. I treated like a true doctor. Physician, heal thyself or right. And so I literally jumped on the table because a colleague of mine had posted about it, that he did his. He's a radiation oncologist in Florida. He tried it out. And so I was like, you know, I have the machine. I know this should work in theory. We just never taught about it in residency. And I look at all the German data, there's tons of. It's like, why do we not do more of this? And sure enough, I'm actually my own personal case control study, because I did steroids and PRP in my left Achilles, and then later on this past year did the right side with only radiation and no steroids. And now I'm walking without a.

Limp. You obviously did the other.

Side. No, no, actually, I didn't. The PRP actually finally did. So I had two cortisone shots and PRP in the left, and then a year later radiated the right. Both of them are holding up pretty well so.

Far. Got it. The other area that is of huge interest for me at least, is the very, very high hamstring tendinopathies. So that ischial tuberosity pain, very, very common for runners, seems to be anecdotally much more common in women than men, based on pelvic.

Anatomy. I've only treated women for some reason with that, and they've all had tremendous.

Results. It's still the same protocol. It's the three gray over six treatments over two.

Weeks. Exactly. For any type of an arthritis, you're essentially lysing all the macrophages and you're eliminating that cytokine storm that would have normally resulted. It's very similar to what cortisone does, but the difference is it seems to be, based on the studies we've seen, it's much longer lasting than a cortisone shift. Not to mention the fact that you're not necessarily violating the capsule. And in the case of an Achilles tendon, you run the risk of rupturing it with multiple injections. So totally non invasive. You just get up on the table. Most of my patients go right back to whatever they were doing. And many of them are actually quite athletic and they don't take any breaks during treatment. They just do what they do. They're still working.

Out. Is there any literature looking at this for spine injuries? By injuries, let me be clear what I mean. So when you think of all the time that people are getting spinal epidurals for irritation of spinal nerves, herniated discs, things of that nature, is there any reason to believe this could have any efficacy there? If indeed there's some efficacy, which there clearly is due to spinal injections.

Or epidural injections, There is some data for spinal osteoarthritis specifically. It's less robust than all the extremities. I've actually done a few cases and it's actually worked quite well. Medicare actually does reimburse for these.

Things.

Things. The issue with the spine is it's such a multifactorial area where if you've got a nerve root compression or a disc issue, I can't fix that part of it. But there is limited data that I've seen out of Europe that did show some degree of relief, but it's not the 80 to 90% that we quote for the extremities. It's probably half that.

Interesting. And do you think it's because of patient selection? Like if you knew you were dealing with a facet arthropathy, that should.

In theory respond well, it should and it does. I've done a few of those. SI joints seem to respond quite well, and that's in the literature that's included. So hips, SI joint, lumbar, spine, those sorts of things, they are described. They're just not as routinely treated. There's not as the level of experience that we do have.

With. But your ability to center the beam is remarkable. You're using the same high fidelity equipment you're using for rad onk. So you can hit a P inside if you want.

To. Well, you could, but that's exactly what you don't want to do because you're basically trying to eliminate all the macrophages in the region. So you're actually better off treating large, larger fields. Just the exact opposite of what we do with cancer therapy. And because the dose is so low, you're not really gaining anything by being too cute with the small fields. You actually want to treat the region. It's like almost like an abscopal effect for the whole.

Area. So if you're treating somebody that comes to you and they've got an Achilles tendinopathy, usually there's a point of maximum tenderness, but it usually hurts up and down the whole Achilles. How do you position the beam? And are you literally hitting from.

Mid calf down to heel from the insertion in the gap? In my case, part of the gap, the inferior gastroc was painful too. So I treated that entire region. The field was probably about that long, all the way down to the calcaneal insertion and even onto the a little bit of the plantar surface of the heel. Because again, when you're talking about these super low doses of radiation, if it was a sarcoma of that area, I'd be treating a tiny little area. But over here, we want to treat the whole region. Most radiation oncologists, if you talk to their experience treating an extremity, it's usually for a sarcoma. So that's a whole different ballgame where you're giving 60 gray to someone who's had a sarcoma in their leg or something, and you have to worry about things like edema. You can have lymphedema of the distal extremity if you've radiated the whole circumference of a leg or something like that. But with these low doses, it doesn't affect any of that. So you do treat large fields. It'll be from the insertion of the Achilles all the way down. If it's a plantar fascia, the entire plantar surface of the foot. Another thing that we see a lot, which is not arthritis, is deputrins contractions and also the foot equivalent, which is leader hose disease. I had to look that one up. That was a trivia question. But it's essentially palmar or plantar fibrosis. And so radiation works well there as well. Very well documented. And that requires a higher dose, though. You're talking about three gray per fraction. Per fraction, five fractions. And then you do it again after a few.

Weeks. So 15.

15. 15.

15. It's almost.

Cancer. Yeah, almost palliative cancer. Not a high dose. But again, that's for fibrosis keloids. It works very well to get teenagers with big old go hanging off their ear after getting their ear pierced and things like that. And so again, you're treating the fibroblast. In that case, you use 4 gray times 3 treatments of 12 gray. Relatively large dose per.

Fraction. And you can totally protect the.

Brain. Totally.

100%. I've seen, obviously, patients with debilitating keloids. What does it look like after the.

Treatment? So the treatment has to be adjuvant after a surgical resection. If you just radiate an intact keloid it's not going anywhere because you don't have the DNA mechanisms of a weak cancer cell that can be wiped out. So kind of like doing a.

Lumpectomy. Obviously, if the surgeon just did the resection, the keloid's coming right back.

The fibroblasts go crazy, and they roar right back. So in order to do it right, a lot of people do it, and they have multiply recurrent keloids. Even after treatment, you have to do the first treatment the same day as surgery. So you're just not letting those fibroblasts get a chance to have any sort of a foothold. So I would literally arrange it with the dermatologist to do the resection, send them straight to me. So we get the first dose in that day, and ultimately the cosmetic outcome is as good as if they didn't have radiation. You'll see the scar wherever it is. We get sometimes kids that have had acne scars all over their chest that have these bumps everywhere, and they were all resected flat, and you radiate them, they just stay flat. You don't see any sort of dermatitis from.

Radiation. I think what's amazing to me is I just think there's too many people that don't know this. I think there's too many people that are walking around suffering either from something that's cosmetically upsetting, like a huge keloid, especially on a visible part of their body. Obviously, everybody listening can relate to some nagging injury. Tennis elbow, golfer's elbow, elbow, Achilles tendinopathy, hamstring tendinopathy. These things nag for.

Years. At times, the data was showing some, like one in seven people in the country are afflicted, and the socioeconomic costs are massive. And there's also, you know, going to your whole quality of life and longevity bias. I mean, we're talking about something that can really affect someone's ability to exercise at all, and it can lead to exacerbation of other medical.

Problems. You know, I was very encouraged to hear you say a second ago that Medicare is covering some of these.

Things and private insurance, too. Yes, for the most part now, a lot of times, because it's relatively new. I'll have to get on there and do a peer to peer with the company, but I've had no rejections at all. Even for the spinal ones, which are a little bit. There's less robust data, but I've gotten everybody.

Covered. So I think the question is, do we need more radiation oncologists? Because how are you making room in your practice to treat these patients, when your cancer patients are probably ringing you off the hook as.

Well. That's a big reason why it hasn't caught on. I think there's a component of just. Just you've got 8 hours or 12 hours a day that the linear accelerator can run. We were busy with that. But one of the things is that, because unless it's a deep hip or something for most of the superficial, for all the other joints, you can use one of those old style orthovoltage machines that I mentioned earlier, like what they use in Europe. They still sell those here. There's a company called Xtrol that still makes them. And they're perfectly acceptable for all the joint stuff, except for the very deep ones, like maybe a si or hip joint. But you could have a small center set up. And those types of machines don't even require the shielding because the energy of the photons is very, very low. It's highly underutilized at this point. And the Europeans have shown us the way it clearly works. And America just has to catch.

Up. Yeah, this is definitely an area where we are way far.

Behind. But it's truly exciting. I mean, I love treating cancer patients. It's really personally very rewarding to tell someone that they're ned. There's no evidence of cancer in their body anymore. Their PSA is low, their mammograms look good. That's what's kept me going this long. But the amount of immediate relief we're seeing from all these inflammatory conditions. Conditions right away, it's a night and day. Patients come in one day, they can't grip a doorknob or lift a gallon of milk out of their fridge. And after six treatments, they can. And they're just. They think you hung the moon. It's an amazing.

Thing. I'm hopeful that people listening to this. So if there's a million people listening to us have this discussion, and one in seven of them, let's just say one in ten of them at some point in the next couple of years are going to experience the type of injury that would benefit from this. How can they go about finding they can't all come to Houston to see you? I'm trying to get you to move to Austin. But regardless of where you end up, they can't all come and see.

You. You already said the answer. I'm just going to move to Austin. We're just going to do this full time and drive cars on the weekends. No, but seriously, there's an uphill Battle, because as I've been going out and trying to get the medical community in Houston aware of it, you have a lot of pushback because, number one, you've got orthopedic surgeons, podiatrists, hand surgeons who are looking at this. This like, number one, what are you doing? What are you talking. Are you. They look at me like I'm crazy. And number two is like, even if this actually works, the concern is with someone's got maybe a knee arthritis that's been nagging them and maybe they're going to need a total knee at some point. Their concern is, wait a minute, is this taking surgery off the table? Which it's not, by the way, because it's such a low dose. There's been plenty of cases of surgery after the radiation. It's not an issue or you're taking away from, like when you had your plantar fasciitis. I'm sure the podiatrist build something for when they do those extra corporeal shock treatments and steroids and whatever it is. It's a different paradigm that would potentially be taking away. A lot of doctors are very negative about it. Most of them at this point are very negative. But I think that tide is going to turn just like anything else. It's just going to take a lot of education, a lot of time, a lot.

Of. Well, I think at the end of the day, look, I don't think patients will have any patience for turf.

Wars. Yes, that's.

True. And so if I'm a patient, every doctor needs to be a fiduciary, Gary. They need to put my interest ahead of their.

Interest. And what's interesting is that I think you can have your cake and eat it, too. The reason I say that is many times this is an adjuvant for other things. So if you've got a podiatrist that's doing all these PRPs and other things, I'm actually looking at starting a protocol. I just treated a nurse in Houston who's a NP who does stem cells off label, but she does them routinely. Has quite a big practice we're going to look at. Maybe you can do radiation with adjuvant stem cell treatment because it's such a low dose. This may be the sort of combined modality thing down the road that we haven't really, really approach where there may be options to do other things.

Still. But again, I mean, for Medicare to improve something is a huge bar. How are you getting Medicare to approve this? Are they basically acknowledging that, well, hey, if Europe's been doing this for a hundred years and it's working. Like, what's their.

Bar? That's what it looks like. You know, I've got the C61, which is the ICD code for prostate cancer, which is in most of my patients. We got the osteoarthritis codes. Now they just go right through, typically without any sort of a problem. Some of the private insurance is you have to get on a peer to peer call. But when I, all I literally will do is quote them a couple of the German studies. Unfortunately, we got a little bit of a setback because there's only two randomized clinical trials that are both heavily underpowered, poorly run studies, just not well done. So that's been a little bit of a setback. And the randomized data may never come just because of the nature of this sort of thing. But having said that, that's not the obstacle anymore. It's really just public awareness. And like you said, just like a guy that doesn't want a radical prostatectomy and wants radiation therapy for his prostate, he's got to be his own advocate. Advocate. And the data is out there, the information is out there. There's a couple of big Facebook groups. One is only Deputrin's patients and they literally will post up there. I've got this big nodule. What do I do? My surgeon wants to cut on me. And so there's actually a whole network now. So there's a lot more of that education going on. They've got big PDF files of doctors all over the US that will do Deputrin's radiation. So Deputrin is a little bit more commonly accepted. But as I'm slowly talking to these folks, they're going to migrate into their arthritis space as well. So I think it'll come. And the general public has nothing but great positive outcomes from.

This. Do we have a sense of the durability of this? So, for example, I have a little bit of osteoarthritis at my AC joint on the right. It barely bothers me. But every once in a while, if I'm doing something really violent, overhead reaching for something, or I play a ton of football with my son, it'll bug me for like three weeks. I'll take a little bit of Advil, it's.

Fine. Right.

Right. If I did a treatment there, would it be done or am I doing this treatment annually? How do I. It.

Worked. There's a lot of variability there depending on what the actual anatomy that's causing it. If it's literally just a straight up osteoarthritis case with no physical structural issue. I've seen cases, I've now again, I've only been doing this about a year, so I don't have the 25 years of experience I did with cancer. But I've talked to, there's a couple of doctors who do this routinely. They've been doing it for 20 years in LA. One of them treated his own neck, shoulder and spine. I think he said 15 years out, anecdotal, obviously, but never had to retreat him. So itself. Typically the German studies allow for two treatment, two retreatments because the dose is so low radio biologically, I don't see any reason why you couldn't do it. I don't know about annually, but, you know, maybe every few years or something like that. But there seems to be a fair bit of data that a lot of patients who don't have other structures like a knee that's bone on bone, it might only last a month or it may not even work. But for the other ones, like the hands and all, it seems like it's certainly longer lasting than any sort of cortisone shot. But I think months are very reasonable and probably years for most people.

People. Now, what about non osteoarthritis like rheumatoid arthritis and things like that? Is there any reason to believe that this could help with the debilitating injuries that those.

Patients. So I've done three cases of rheumatoid arthritis and one guy that had a gouty arthritis as well, because again, it's a systemic disease. I'm not going to pretend to be able to cure that with a local treatment. But to a single knuckle that's driving them nuts? It's still an inflammatory process and yes, it works great for.

That. So if a patient has rheumatoid arthritis where they're really experiencing a lot of deformation in the hand, you think you can help that patient with the local part of.

It? Yes, it won't reduce the deformation necessarily because a lot of that is long.

Standing. But if they were treated early enough in the course of the disease.

Yes, I think there's no strong data to support that, but I don't see why it wouldn't work personally. And it definitely, from a purely palliative standpoint, just to reduce pain, it does work. You have to manage their.

Expectations. What are some other examples of where this could be used, at least in your experience so far, in terms of reducing reliance on NSAIDs or opioids or other things.

Like. Like that tennis elbows become a big one. Doing several of.

Those. How far down the arm do you.

Irradiate? I base it on where the patient when I. If they palpate, if they're getting pain down into the brachioradialis, and if it's radiating further down, I'll treat a larger field because again, there's no reason not to. Bigger fields are better. No need to.

Be. And again, it's just.

Six. Three gray. Three gray. So. And again, that's three gray. Locally, it's to an area where there's no vital organs nearby. The total body dose is negligible. It's like getting a CAT scan initially for the rest of the body body. So I would treat definitely the joint capsule, a little bit of the distal humerus and the proximal radius and whatever else. But if it's hurting larger, I'll just treat a larger field. In that case, we use opposed lateral beam. So the patient will just lay there. The beam will come in from one side and rotate around from the other side. And we treat them both because that way we get the same type of homogeneous dose we do with our cancer patients. I've actually done several piano players that have De Quervain's tenosynovitis and their wrist. Wrist, because when you're stretching to play those notes. I'm a musician as well. All my musician friends are coming to me. The wrist pain is going away very quickly. My biggest patient cohort so far are former patients because they don't have radiophobia. They're like, I've been through 80 gray to my prostate. This is a joke. I'm bringing my wife with me. And half the times the wives sit there for their daily treatment anyway, and they start chatting in the lobby. So we do the wife's hand the same time we're doing the husband's prostate. And for the most part, the hands, the wrists, the elbows, it's very rapid. In the case of the tendonitis, like my Achilles, it was a couple of months. But that's not outside of the window of what we've been conditioned to expect from all the German studies. So it can be not as immediate of a relief as a steroid shot, but it does seem to be more.

Durable. Yeah. We failed to mention at the outset that you're also a remarkable musician. How much do you still play the.

Drums? I got a couple of. Actually a couple of doctor buddies. We get together and jam every week or two. And one of them is actually a guy now who's actually got his own YouTube channel and Spotify. And he was actually a professional musician before becoming a cardiologist. So we may actually start touring again. But back in the day we had a full doctor band, a full 70s rock cover band called Ultrasound. Those are the good old days. We used to play Journey and Rush and Led Zeppelin all day.

Long. Yeah. I was commenting recently on a podcast how much I regret not seeing.

Rush during their last tour again because of a gbm. Tie it back into what we're doing here. Neil was a.

Genius. So greatest drummer of all time. Are you going with Neil? Are you going with.

Bon? Neither. Because I went to college here at UT and that opened my entire eyes up to the world of jazz. So the jazz drummers can all drum circles around those guys in terms of pure technical ability. But yeah, feel rhythm. Not necessarily being able to wow people the way the jazz guys can. But yeah, Neil and Bonham are both right up there on the rock.

List. Would you put them at the top of the rock.

List? I would put Neil first. I'm just partial to Rush and a lot of that has to do with their music. Not necessarily now. Neil was obviously an innovator, but as a 16 year old, I'm sitting there trying to imitate every single note on his drum solos. Everything like that. Neil number one, Bobanum and the new generation rock guys are incredible. The guys that grew up with Neil as an inspiration. You've got 12 year olds who can do this stuff in their sleep. And then all these math metal bands. You got Dream Theater and things like Animals as leaders. Some of these guys are doing things. I pride myself as a drummer. I'm able to analyze the music really well. It's getting to the point where it's almost more math than music. Like it's so, so intricate, the modulation of the time signatures and things like that. It's actually getting beyond where even I'm having trouble understanding it.

Now. Can you appreciate it from an auditory perspective? Does it get too technical where it's hard to appreciate and.

Distinguish? That's a fine line. Because when you think about it, music is just math with emotion added in. And it gets to a point where some of it is not appreciable anymore, at least not to me. Some of these guys love it, but that's where the jazz side comes in, where it's all about fit feel. But even the jazz guys will be extremely talented in terms of their ability to feel the beat and have it be pleasurable to the ear. But they're doing such intricate things. And when you can balance those two things out, that's heaven as far as I'm concerned. When you can have the emotional side and also have be technically challenging and not just playing a straightforward. The straightforward stuff is great too. But it gets a little bit tedious.

Sometimes. So we met actually driving AMG.

Drift Academy I think it.

Was. Yeah, yeah. Which by the way, not to crap all over over it. I ended up doing it because at the last second I got a phone call from my driving coach and he was like, hey, I'm doing this AMG driving school. And they got an extra spot in the advanced drift school. Do you want to come? But I'd already been to the drift academy with my friend Josh Robinson. I was like, yeah, sure, I'll go. And I was like, well, this is the last time I ever do one of these.

Schools. Josh's school is 100.

Times. It doesn't.

Compare. Not even.

Close. If you want to learn how to drift. Yeah, if you want to learn how to drift, you go to the Texas Drift.

Academy. I want to go to Minnesota with them and do that ice.

Class. Are you going on this.

Run? I don't know if I'll be able to make it or not. I'm trying.

To. Yeah. Yeah. Anyway, we met, but it was totally.

Random. Well, I knew who you were because I've been a member. I've been a follower for years. I was like, that's Peter ATI over there. So luckily we got paired up in the same group. And that's kind of where it started. Was totally random. I was actually just. It was a last minute thing that was actually a level two. So I was like, you hadn't.

Done the level right, right.

Right. So I was like, man, how did this guy get in here without even doing the level one? So having done that, I agree. Especially those cars with the automatic transmissions and the turbo lag. Not the greatest for.

Drifting. Yeah, yeah. You've been kind of a car nerd your whole life. Life. What is it about cars that has you as excited as you.

Are? You know, I think whenever anybody asks me that, I kind of think about it in terms of every three or four year old boy is enamored by cars. But normal people just grow out of it and some of us never do. My dad certainly liked cars. He taught me how to change my oil and whatnot. But he wasn't a fanatic like I am. So it just kind of started there and then it got to a point. Where like my parents will tell you the story that was that 4 year old who could tell you at a car driving by if it was an Oldsmobile that had Cadillac hubcaps on it. Like how the hell does this kid know that this thing. I don't know where it just kind of clicked over the years. It was always just a nice release. I guess being a mechanically oriented type person. I think if I didn't do medicine, I would have done engineering. Which is why I said, what.

Did you study in.

College? I was actually biology. I did a BA with art. So I did a lot of jazz studies at ut. So I was a music guy. Engineering just seemed fascinating to me. You know, I was always interested in medicine from day one. But I think that really the mechanical side of things, like knowing that every car's five gear ratios and what their torque converter lockup is and what their horsepower and torque is, it's.

Just. And what posters of cars did you have on your.

Wall? The same as everybody actually. No, because everyone had a Countach, right? I never had a.

Countach. See, I had a Countach. What did you.

Have? I mean, they're cool. I would have like a Callaway Corvette, Miami Vice, Testarossa 928, which I'm almost done with my old 928, getting it back on the road. More of the domestic stuff, the stuff that's more attainable. Fox body Mustangs, the 5 liter Mustangs of that era are really cool. C4 Corvette, back in that era when they were state of the art. I mean, I loved watching Knight Rider, so I thought Pontiac Firebirds were super.

Cool. It's funny, I just bought my youngest, his first Lamborghini poster. He's mostly got sports posters on his walls, which is great. But I was like, you gotta have a Lamborghini poster. So let's go pick one out. So we scrolled Etsy for hours. Cause I wanted to figure out what his taste was. Did he want to go retro? Did he want like a Coontex? But in the end I think we went with. I can't even remember now. Actually we just ordered it. I think we went with an Oricon or.

Con. Yeah, modern.

Car. Yeah, it was going to be an Aventador or an Huracan, but get the color right and get the angle.

Right. Have you driven a Countach.

Yet? I've never driven a Countach. Have.

You? I have. It's one of those don't meet your heroes kind of things. It's cool, but it's kind of a pos too. You know, it's. The bar has moved a long way since then. It's for the.

Experience. I mean, you clearly don't expect it to perform like a modern car. But even if you, you judge it for what it was in the 80s, is it still not.

Enjoyable? It's enjoyable because of the 80s campiness in retrospect. But even compared to its contemporaries, you look at an 80s 928 Porsche or even a Testarossa, those cars are beautifully driving, you know, long distance cruisers, super comfortable compliant suspensions, you got good ergonomics. And the Countach is so awesome because it has none of that. It's awesomely.

Bad. Yeah, yeah. I've driven a Testara. Have you ever driven an.

F40? I have not. Would love to have ridden in one, but I haven't driven one. It's a race car. You're basically just sitting on the ground with a carbon tub around.

You. So if you could have three road cars but you can't sell them, you're not making the decision based on economics. What are the.

Three? You want three road cars, not daily drivers. Are we talking about just three cars? That's all you can have in your.

Garage? No, no, no, no. These are your three grail cars.

Cars. Okay. I would probably say, man, there's too many to choose from, but to go with, it's going to sound like a cliche, but McLaren F1, I mean, how do you not pick.

That? If I could only have one that's the one I.

Want. It's got to.

Be. I sent you the picture of me sitting in that.

One. I was jealous. Oh my God. That would have to be number one. But then there's at least 10 that I could pick from. Be happy. But I would probably say, and one of them is one that I have a lot of experience with is the Ford GT. I just think that's Gen 1. Gen 1, one of the all time great rates. I would probably pick stuff that's manual and somewhat analog. So I'd probably have to say Carrera GT. Porsche Carrera GT with an NA V10. They're unobtainium now, but they were reasonable of just a few years ago and they're just. There's plenty of faster.

Cars. A Carrera GT today is going for about.

1.718. 10 years ago it was half.

That. Yep. And what's an F40 going for.

Today? It's gotta be three, I think, at least. Yeah.

Yeah. I mean, six, seven years ago it was half.

That. Yeah, it was half that half.

That. Do you think this is a bubble or do you think these things are not coming down in.

Value? They're never making any more of those. Limited supply, demand is never going to wane for those at least. I think when you look at other collector cars, like some of the pre war stuff, it's going down because the target market is all unfortunately dying off. Those people aren't around and who appreciate that and that may happen at some point. I suppose there's going to be a point where nobody cares about this. We'll probably be long gone by.

Then. The McLaren F1 is unattainable and there's so.

Few. That's in a completely different league than the other cars. But even like something that Ford GT, they made 4,000 of them. It's not that.

Rare. But a few of them are.

Gone, A lot of them are gone thanks to lack of traction control. But still, I don't think they'll ever go down just because that era, I think the Gen 2, the current Ford GT, which is a twin turbo automatic car, will ultimately be eclipsed in value by the old one. Even though right now there's still more. They're almost double or triple, but I think it's going to go the other.

Way. So where would you put the 959 on this.

List? We talked about that a little bit, it's right up there. The only downside to the 959 is that it was so ahead of its time. That essentially is what a modern Porsche is now. So yeah, it's super cool. You've got the 80s campiness, the looks, but it's basically like driving a 993 Turbo for the most part. It doesn't have that NA V8 or V10 sound. It's a turbocharged flat six. Like everything was after it at that time. There was nothing like.

It. Did they have four wheel steering as.

Well? You know what? I think they.

Did. It was so modern.

Modern. So modern. Sequential turbos and even water cooled heads, even though those were all air cooled Porsches back then, they managed to water cool the heads. And now Canipa does a really cool version, the restomod version, but those never came to the us. I think you know about that, right? It was the Bill Gates rule. Did you hear about.

That? I did know about this. Say more. Say.

More. I don't know all the details, I should have read it. But essentially he was able to get the gray market to passage for these cars for some loophole. I don't know the details. Of it. And only after that were they able to import them into the us. Of course, now that they're older, you can get anything under a 25 year old. I like the oddball stuff like that. That's just unavailable. The 959, I would still put a click below the Carrera GT just because of that naturally aspirated F1 derived V10 that just sings. And the 959's motors doesn't have that level of.

Character. I'll tell you what's interesting about the Carrera gt, which by the way would be on my list of three as well. Most people listening to us now, if they're not car nerds, wouldn't spoil bought a Carrera GT if it ran over their.

Toes. Yeah, that's like a bigger Boxster, right? It's just.

Like. So they're like, is that a Porsche? What is that car like? That doesn't even look like. It doesn't stand out at all. Whereas if you saw a McLaren F1, you don't need to know anything about a car to know you saw something.

Special. For sure. For.

Sure. And I think the same is too with the gt. The GT is absolute head turner, no matter.

What. And the interesting thing there is it's really based on a 60s design. It was a tribute. Tribute. But Camillo Pardo, who was the designer for Ford, who basically reinterpreted it for the 21st century, kept that original character, but made it aero friendly and was able to use all these hard points from the old car, but make it modern and basically upsize the car. It's like 110% size of the original that you could actually fit two people in. Because the original GT 40s were tiny and they apparently generated tremendous front end lift in Lamar. And the modern one, I've actually run at the Texas mile and on an airstrip over 200 miles an hour, it's dead straight. They did everything right without resorting to the modern cars with all the big wings and all the big downforce, it's just well.

Balanced. It.

Is. It's just. They just did everything right on that.

Car. Okay, now of the modern cars, anything that you really, really fancy, let's define that first wave of hypercars in the 2015. So when the LaFerrari, Ferrari, the P1 and the 918 came out, which is 2014, 2015, so 10 years ago.

They call it the Holy Trinity for some.

Reason. Yeah, golly, that was staggering.

Right? It.

Was. So from that era forward, what.

Do you fancy the Most those cars again, at that time I liked them more than I do now just because again, the hybrid technology is leaving those kind of. They're a little outdated now. I think out of those three I was personally, maybe I'm sounding like a Porsche fanboy, but the 918 was just stunning. Part of it was just the design, forget about the performance. And it had an again, Nav 8 high revving bespoke to that car, not in any other platform. And the electric component was just the gee whiz thing of the moment, which of course made it ungodly fast. But that NA V8 and the way the exhaust sticks out of the.

Back. Well, that's why, by the way, I've got a friend who has all in silver 959 Carrera.

GT. That's the Trinity right.

There. Like that's a.

Trinity. That's like having, you know, F40, F50, Enzo LaFerrari. Same sort of thing. I mean, all of those cars were amazing. But since then, the interesting thing about that era a decade ago was that was probably the inflection point after which performance doesn't matter.

Anymore. Who cares? We've saturated.

Performance. Who.

Cares? You're traction limited at this point.

Right? And not only that, you can buy a used EV, you can buy a Tesla Plaid that'll do 60 in two seconds flat. 50 grand, that'll smoke at.

Everything. Tell everybody about the time you took your Tesla plaid to coda before, how long did it take you to smoke the brakes on.

That? So when it was stock, one.

Stop. Incredible stop. Make sure people understand this because they don't know. So that means you came out of pit lane, right? So you're going up to turn.

One. I didn't outlap, so I didn't outlap, so. But, but the first coming down. So the first hard brake, hard.

Break is going into turn.

One. Going to turn one. And my buddy was in an SF90, which is a thousand horsepower Ferrari high hybrid, which is basically the fastest Ferrari you could ever buy. I was catching up with him in 20 and coming down the front straight, I caught an SF90 in my daily driver. But I nearly rear ended him because the car was able to stop just barely for turn one, but the brake fluid boiled at that point. The car was not designed to do that, unfortunately. And what's interesting is you would say, okay, it's an electric car, it's heavy, blah, blah, blah. Other electric cars don't do that. The lucid, the taycan, they actually have really good brakes. But at the time time I didn't realize this because they had been advertising as being track ready or at least able to run a like they're talking about how it ran so good at the Nurburgring. But the factory brake fluid is DOT three, I find out after the fact, which is low boiling point just boiled it. The car is designed for efficiency, low.

Drag. I didn't even use DOT three in my.

Simulator.

Right. I was running dot four in the.

Sim. Probably boiler simulator. Yeah, yeah, yeah. So a 5,000 pound machine stopping from 100 and I probably did 160 on the front.

Straight. I bet.

More. Yeah, that's about. I think it was limited actually that time didn't have a track. The amount of BTUs that you're trying to shed off of those brakes, just forget about it. So thankfully it.

Had. So the brakes are fine if you put better fluid.

In. Well, they're better, they're less.

Terrible. But if you want to track a plaid, you're going to need new.

Brakes. Did I tell you what I did? I ended up having a full Wilwood setup put on the car. So all new rotors, custom ducting. Mike Dussold du Sol Designs. Actually he bought a plaid for himself. He's the guy that built the Z06. I'm driving now. But he ducted into the front brakes, basically. Custom brake ducts. That car is sealed. The whole front end is sealed. Okay. It's not meant for that. It's meant to just be.

Low. So you weren't getting any air on.

Them. Nothing. Nothing at all. So he actually made custom ducting and after that the car was unbelievable because you could actually late brake and do really.

Well. So what lap time can you do in a tripped.

Plaid? Now here's the problem. You can only get one solid lap before it starts pulling power due to heat to the.

Battery.

Okay. But my best was a 225 and so that's at a 5,000 pound car. That's no weight taken out. Just a stock car. I didn't do any mods to other than just the brakes. But you do one lap just to re answer your previous question. I don't know how much time we have, but I'll just keep it brief. That one stop, turn one brakes gone. Thank God I have regen. So I just literally nursed. But I was already. I couldn't turn off. So I go through the S's and I'm just 30 miles an hour. Whatever I got down to the regen is enough to keep the Car from completely just going off the tracks. 30, 40, 50. So coming through 9, 10. Coming into 11 again. I'm not on the throttle at all. I'm just maybe going 40 miles an hour. But the Regen has coming down the hill towards 11. The regen has kept me from gaining any more speed. My right foot is on the floor, the fluid is boiled. So I had to go wide in 11 into the gravel, completely around. And then, you know, that's when I found out about all that and the McLaren Senna both taught me where all those orange squares are spray painted on the armco where you can have the emergency on the offs. So I literally went through the gravel, came within inches of the arm coat 11 and then just hobbled in. But then after that, the next time out we put DOT four, put Castrol brake fluid in it and changed the pads. Then it was good for maybe a lap. So then ultimately that still wasn't good enough. So we did the big.

Brakes. Now I see guys out there with Teslas. They're clearly not pushing as hard.

As you or they're mostly model threes. The model three is 800 pounds lighter. It's not as fast, but it's a way better track car. So I've got dozens of laps in Model threes. They do four fine because they're not making a thousand horsepower and they don't weigh 5,000 pounds. They still will boil their brakes. But if you just do pads and fluid, that's actually a very desirable especially if it's a little bit damp outside. Not much can keep up with you in a Model 3. And autocrosses, they've won national championships with just coilovers in a 4,000 pound sedan. That's where EVs have gotten. But just to answer the previous question, we did the brakes on the Model S and then once that was done, the only thing that eliminated the brakes as the weak link, but the battery, the cooling is still not there. So you got guys spending tons of money. I actually was looking at doing a really heavily modified aero Tesla Model 3. Like Randy Pope's drives, it'll only do a lap at Coda, it's such a high speed and high braking, but you can hot pit and go right back out and you can keep hot pitting, but you'll never get a lap. You'll never get a full lap time, but it'll do just fine if you do that. But the next gen cars, the Porsche Taycan, even the lucid Sapphire, now those cars, they're just as heavy, just as Powerful and they can do.

It. Have you taken the Taycan Turbo S.

Out? I did when it first came out in.

2020. And what'll that.

Last? At the time I was on stock tires and everything. Probably a 2:30ish. Yeah, right, right around there. I think I probably sent you that video. At John Hennessy's track. I had the Taycan, the lucid and the plaid all lined up on the drag strip. I'm in a 750 horsepower Porsche that can run tens in the quarter mile. And the plaid and the lucid walked away from me like I was on.

Foot. You just didn't have the traction.

Control? No, it didn't have the power. 750. 750 horsepower versus.

1100. How much does the lucid.

Have? This was the old lucid. Now the new Sapphire Loose has more, has 1200. But this was 1100 and it's still a tenth or two behind the.

Thousand horsepower because they all have great.

Traction and they're all, all wheel drive. The traction is a non issue all the.

Same. It's literally just power to weight at that point. So I didn't realize that. So the Taycan Turbo s was only.

750. When you stand on a Turbo S, if there's a plaid next to you, he will leave you like you're not moving. That's like the Audi is a super fast car in the real world world. But that's why horsepower doesn't matter anymore. But that was more horsepower limited. The Taycan would happily do. And actually I had a turbo before the Turbo S which had steel brakes, Turbo S had ceramics and even the turbo would do it on all season tires. The very first Taycan that came out, this was in the early days when Porsche was VW was having to respond to Dieselgate, you remember Diesel gate, that whole deal. So they had to build these electric cars and they had to go to states that were carb basically the California Air Research board emissions compliant because of all the diesel diesel penalties they had. So the first cars didn't come to Texas, they only went to New York. So I got a non Turbo S, a regular Taycan one all season tires out of New York and on steel brakes. Porsche is Porsche. I mean it was squealing in the corners of an all season tire. But it lapped 20 minutes, no problem. Brakes were solid. There's just something about the German engineering there. But having said that, the Lucid is now equally good, if not better. Despite being a brand new non legacy company who is again not trying to build a Track car. But the lucid Sapphire is faster than a plaid. Now it runs eights in the quarter mile, but it can actually track. And even my old lucid, which I was expecting to it can run.

Eights in the quarter.

Mile. Yeah, it can crack in sub nine. Now it's several car lengths ahead of a plaid, which is beyond bonkers. You have to warn passengers. These cars now, you can't just accelerate on them. You have to say, hang on, just put your head against the headrest before I concuss.

You. By the way, we failed you very, very briefly mentioned it, but my favorite car post the holy trinity of 2014 is of course the McLaren.

Senna. The Senna.

Yep. How does the Senna stack up for you and what was your fastest lap time in a.

Senna? So my best again, the biggest limitation of the tires are limited the non gtr. The Senna GTR can probably. I've seen guys run like I think two flats in those things. I know a coach of mine had run a 208 just barely even tried. But the street Senna on the Trofeo R just, it understeers. It's really just not meant for that. But it'll still. And it got tons of downforce, tons of braking, but it just doesn't have the grip. So I think the best I did was a 215. And again, when you're driving a.

Car that value, that's insane for a street car with street tires, that is.

Insane. But at the same time, I'm sure a pro could do better. I was still thinking, you know, that arm code gets really close to the car of this.

Value. It could be a breaking into turn.

12,150. Even on Trofeo I cars, McLaren doesn't want you to put slicks on it. And so I violated all the rules and I ended up putting a set of Pirelli tires off the Ferrari challenge cars on it when I first put it Again, slicks need camber. You can't get much camber out of a street Senna, which to me was the most disappointing thing. Whereas the GT R, you got 4 degrees even without camber. When I first stopped on that back straight, completely stock Senna with just slicks on it. At the 150 mark, I almost parked it in the corner. It was incredible. Even with the Trofeo R to stop at 150 in a car that in a tire that drove me to Houston and and back. The bandwidth of today's tire, that's a whole nother topic. It's incredible. What? Even an all season Michelin can generate 1G. 1G is nothing anymore. All my old car and drivers, I have a library of Thousands of magazines. 0.8, 0.9 was a huge deal 30 years ago. Now you got minivans that do that. And even all season shod sports cars that are heavy can do that on a regular tire. The chemistry of these tires these days is.

Unbelievable. Yeah. And the Pro Mazda, we're.

2.32. Yeah, yeah, right. I mean, that's.

Just. And that's not even on a Pirelli. I'm a cheap guy, so I.

Run.

Yeah. Well, at the same time I run.

Hard. AMG GT3, I was running hankooks, which would at least last me two weekends. And even then, like that car was running 211s on Hankooks with just me driving it. So the pros are running faster than.

That. Yeah, I think Senna gtr, not a streetcar, of course, but just the.

Problem with the Senna street car is it's too track for the street, and it's too street for the. The 720s, which is mechanically identical without all the downforce, is a beautiful GT car. Drive it cross country, you can store stuff in it. Super comfortable. And on Hoosiers, not on slicks, but on Hoosiers. And I changed that to steel brakes. That's a 216, 217 car. It's not that much.

Slower. So faster than like your old.

GT4. Yes, the McLaren GT4. That one, I'm sure. I think Randy Popes could probably run close to that. But when driver to driver, driver to driver, three seconds probably. And that's all in the straights because the GT4 car has half, not half the power, but it has. And actually my GT4, I cheated. I tuned it. The 570s GT4 was already detuned from the street car, but you can tune the street cars as well. So when I was, I pushed an extra 150 wheel just by tuning it, because stock turbos can handle that. So that would go 175 on the back straight. Whereas a regular GT4 can do 20 miles an hour less than that. But Even then, the 720s. Actually 720s and Senna are identical on the back.

Straight. The Senna can stop later.

Though. Stop.

Later? Yeah. The Senna you can stop on. You can wait till.

100. Yeah. In the 720 with the aftermarket steel brakes, pads and a Hoosier. Not even a. Which is still a DOT tire, you can still break it a little bit after 200. It's not bad at all for a car that you can go shopping at the outlet malls in because it's got a massive frunk and the ride compliance. That's the biggest thing about McLaren. So the Senna is more tied down, but they all have that active suspension that doesn't use sway bars or springs. It's all hydraulic. It's all fully active. There's hydraulic lines that diagonally connect the front right to the left rear wheel. So the pressure in those lines combats body. So you can have it be a plush highway ride, or you can have it be a stiff track car. The bandwidth is almost unobtainable in any other.

Car. Do you think McLaren is somehow underperforming relative to what they should be doing, given both their quality as an automotive brand and as a racing.

Brand? Underperforming in terms of sales? Is that what you're talking about? Primarily? They are, yeah. They truly are. And a big problem is, I think, is the perceived. Actually, it's not just perceived, the actual lack of reliability. I love the cars, but they're always. It's all the jokes about British electronics. They all come to bear. Even the Senna would go into limp Mode on between 9 and 10 if you floored it. It wasn't just mine. We had Sena Fest going on with 20. I think we had 20 on track at one time. Some guys were just kind of tooling around, so they were fine. But if you were hauling ass between 9 and 10, when you get a little bit of suspension.

Droop.

Yep. You would go into limp mode if you're accelerating through that. I would.

Literally. Even a.

Gtr? No, no, I'm sure the GTR is fine. I haven't tracked one of those.

Unfortunately. Is that a mode.

Issue?

No. Like, if you were in track.

Mode. That was in track mode. I think it happened to me even one time I forgot to put it in track mode. I think it still did it. It's a G force related to suspension droop issue. They just freaked out the computer. And they had McLaren guys on site who were actually working on.

Patches. And they could patch.

It. They did. I think it made it less frequent, but I think it still happened after the patch. I have to ask the McLaren guys about.

That. Well, I think it's safe to say nobody's listening to us anymore now anyway. But in case anybody still is, this has been an awesome.

Discussion. I really appreciate the offer to come out here. This is a true privilege. Peter, what you have done in this community is unparalleled in terms of I think I told you when I first met you I was like dude, how do I get CME for this stuff? Your lectures are better than almost all not lectures, but your podcasts are better than Almost all the CMEs because you get the right quality people on here. Much better than me by far. And the way you phrase the questions and the way you parse everything, it's so understandable for a wide bandwidth. I got my non medical friends and family all the way to the colleagues everybody gets get something out of them and that's hard to.

Do. Well hopefully today we delivered a lot of insight both to people who are obviously interested in radiation therapy for cancer, which unfortunately is going to be a lot of people. And then of course this other application around the treatment of inflammatory conditions, which again, inflammation lies at the root of so many other things. And just in case anybody cares about a little drumming in cars, hopefully we got something.

Too. I think we have a whole indication for a whole separate series here here. That truly is the drive. If you want that, we can do.

That. All right, well thank you.

Man. Thank you.

Peter. Thank you for listening to this week's episode of the Drive. Head over to Peteratti md.com shownotes if you want to dig deeper into this episode. You can also find me on YouTube, Instagram and Twitter, all with the handle Peteratti MD. You can also leave us review on Apple Podcasts or whatever podcast podcast player you use. This podcast is for general informational purposes only and does not constitute the practice of medicine, nursing or other professional healthcare services, including the giving of medical advice. No doctor patient relationship is formed. The use of this information and the materials linked to this podcast is at the user's own risk. The content on this podcast is not intended to be a substitute for professional medical advice, diagnostic diagnosis or treatment. Users should not disregard or delay in obtaining medical advice from any medical condition they have, and they should seek the assistance of their healthcare professionals for any such conditions. Finally, I take all conflicts of interest very seriously. For all of my disclosures and the companies I invest in or Advise, please visit PeterAttiaMD.com about where I keep an up to date and active list of all.