The Truth About Liquid Biopsies & Full-Body MRI Cancer Screening

Welcome back, everybody. We're going to start doing some of these short little mini episodes, maybe 10 minutes, where we'll talk about some interesting topics. Today we're going to talk about some cutting edge screening tools, like liquid biopsies for cancer, like whole body MRIs, and talk about how useful they are. So in the precision medicine world, the personalized medicine world, we've always wanted to be able to screen for cancer, screen for heart disease earlier. You know, we had, back in 2000 when I was doing my training, the idea of a cholesterol panel, ldl, hdl, triglycerides. Oh my gosh, we can now screen for other things. You know, when the A1C first came out, it was 1996. Actually, an endocrinologist I was training with at that point in time was so excited about this thing called a 1C. You know, it was super fancy. It took like 20 years for Medicare to start paying for it. We've always wanted to find early screening tests. One of those actually was virtual colonoscopies. Back in 2007 and 8 when I came back to Richmond, there's some local groups doing virtual colonoscopies screening for colon cancer. Hey, guess what? You don't need a scope and you can screen for colon cancer. It didn't pan out for a lot of reasons. There's a lot of radiation exposure, screening for pancreatic cancer, abdominal ultrasound, you're not covered by insurance. It doesn't always work the best. How about blood tests, you know, checking for CA19, nine, you know, Alpha Feta protein, other tests for screen for cancers. We've always been trying to find cutting edge things to help us find stuff earlier. And when I was doing some trauma surgery training when I was in the military, I came across this thing called bombant syndrome. Victims of modern imaging techniques, they talked about this in the hospital, the trauma surgery world. And the idea is that because we have cool technologies, we want to use them and we don't always appreciate the errors in them, the accuracy. And there's a thing called a number needed to treat, which is how many people do you have to do this procedure on to actually save a life? And sometimes those numbers needed to treat are pretty, pretty bad. For example, is using Zocor to prevent cardiovascular death in high risk individuals. The number needed to treat over five years is 40. So you have to treat 40 people who've had a heart attack or coronary risk equivalent for five years to prevent one. When you say it like that, it's not super impressive. You know, doing CT scans for cancer. So the point is that we've always been on this quest, how can we find cancer earlier? It's not new. You know, sometimes we have these little screening things we have in the Richmond here, the lifeline screening where you can get an aortic aneurysm screen done. Well, actually that was beneficial. And now Medicare will pay for a screening abdominal ultrasound to rule out an aneurysm in men who smoked. Not for women, but men who smoked. We started doing CT scans, you know, unofficially, screening for lung cancer and actually could find it earlier and actually save lives. And eventually we got some guidance to actually allow for low energy CTs for screening for lung cancer. So there are some things, you know, coronary artery calcium scores, there are some things that are out there, some are paid for insurance and some are not. But two of the newer things right now are liquid biopsies for cancer. There's a couple different tests out there. I'm not going to mention names because I don't want to draw too much hate, you know, but that's a new thing. And the liquid biopsy, the concept is in the one particular test is using this thing called cpgs. It's methylation sites on cells. And you can actually figure about 50 different cancers people may have. And just the next generation of cancer screening, you know, we've been using things like alpha feta protein for ovarian cancer, colon cancer, and extra testicular cancer. And then We've been using PSAs for prostate cancer, CA99s, CA for colon cancer. The thing with some of these tests is that they're not really good for screening. If someone had cancer and was positive, then you could actually use it to track treatment, but it's not really good. So the newest generation are these liquid biopsies, which are now the rage. But there are a couple issues with these. The first thing is that the false positive rate is about 58%. So what does that mean? It means if you do the test and it's positive, 58% of the time, it's not a true positive, it's a false positive. So if it pops positive for a colon, breast, lung, prostate, you know, pancreatic, whatever, 58% of the time, after additional screening, CT scan, MRI, maybe a biopsy, who knows, the results are negative. The other thing is that it's 70% false negative Mal cancer. So if someone has a stage 1, 2, 3 or 4 cancer, 70% of the time it's false negative in all those cancers. Now where the utility comes in is in stage three and four cancer, the stage one sensitivity is about 16%, which means if you have cancer, it's positive in stage 1 16% of the time, which is when you want to catch cancer. So that earliest cancer that you want to catch, it's positive 16% of the time. And as you go on to stage four cancer, the sensitivity is up to 90%. So this is a great screening for stage four cancer. But then the question is stage four, that's usually when it's spread, like, are you actually saving lives? So the advantages are that look for 50 different types of cancers, but it's not really quite yet ready for prime time. I understand people wanting to have a screening test. If it's negative, I mean, you get peace of mind. But again, if people are found to have cancer and they look back, 70% of people, stage one, two, three and four, would have a false negative. If you have stage one, 16% of the time, it's picked up. If you have stage four, 90%. And so again, not super amazing. There's another thing called a whole body mri, which has become really popular in Richmond right now. Where I'm at, there's only one, one way, one group you can actually get that with. Yeah. Otherwise you have to drive to D.C. to get it. But the thing about whole body MRIs, which have been around for maybe eight or 10 years, is that it picks up absolutely everything. About 4, 40% of women in their 40s to early 50s will have a cyst on their liver if you do an MRI. About 40, 50% of adults over 50 will have a cyst on their kidney. So if you start adding up cysts, liver, kidney, gallbladder, pancreas, you'll see a lot of people have these things, these normal abnormals that aren't cancer that didn't result. Again, vomit. Victims of mind imaging techniques should do a test that comes back positive. Then what's next? You know, I want early cancer screening just like everybody else does, but at what cost? You know, I always refer back to the mammogram example because it's not amazing, it's not a prevention, it's early diagnosis. Because by the time most women have already had cancer, anywhere from one to two years, by the time it pops up on the mammogram. So it's not the best breast MRI is amazing for picking up. That's actually a true screen test, but it picks up everything. So you have even more false positives and maybe more biopsies done. So the question becomes, at what point in time does A screen test actually save lives. And that's where the whole process of vetting, you know, the utility of colonoscopies, the utility of mammogram Pap smears. I mean, Pap smears are an example of something that in the 1950s, the most common cause of death in middle aged women was cervical cancer. And in my career I've never had a patient die from cervical cancer. And the difference has been Pap smears. So there are screen things we have are absolutely amazing. If you can deal with the uncertainty, if you can deal with the stress of knowing that you have, you know, PSA for. I think it's a great example. I have patients who, you know, have a PSA 5, 6 or 7, they get a biopsy, it's, you know, Gleason 4 or 5 early prostate cancer. Just watch it. Because 60% of men that are 65 or older and 80% of men that are over 80 will have prostate cancer. They die with it, not of it. And so we're getting used to this in certain situations, but like with a lot of female cancers, BRCA genes, for example, is another great example. You know, why don't we scream everybody for the BRCA gene? Well, in the 1950s, if you had the BRCA gene, you had 20% risk for cancer. Now it's slightly over 80%. And so now if you have a BRCA gene, the treatment is bilateral mastectomy, preventively bilateral salpingectomy, they cut off your ovarian tubes. It's pretty aggressive. And so you also have to weigh the risks and benefits. And I talked about this earlier, that medical error is the third most common cause of death. And so when you start thinking about things we do to prevent, you have to take that into account. That's the reason why you have to work with someone who's really educated, who's trained, who understands all these nuances. You know, doctors were clinical scientists. We like using fancy new technology, but it's not always the best thing for you. So just keep that in mind. As you're reading about liquid biopsies, as you're reading about whole body MRIs and other screening tests, take a deep dive and really talk with your practitioner, your physician. Are these things useful? Is this actually going to help save your life? There are things like screening A1Cs blood pressure, doing advanced lipid panels, looking at your LP, looking at particle membrane size. There are so many things that can be done that actually have utility. Looking for inflammatory markers, SED rate, CRPs. There's so many things that can be done that have, you know, homocysteine levels, nutrient levels, omega 3 levels. You know, taking Omega, taking fish oil lowers your risk of sudden cardiac death 50% and you start looking at people. I routinely check this on patients and they probably half of my people right now have low levels. There's so many things you can do that have a big bang for your buck. You don't always need to do the most recent fancy thing to get the benefit. Hopefully this information was helpful. We loved it. Love your comments. Please share us with friends. If you have other things you'd like to hear us talk about, please let us know below and we'll talk to you all soon.