AMA #25: Navigating the complexities and nuances of cancer screening

**Peter Attia** (0:11)
Hey, everyone, welcome to a sneak peek, Ask Me Anything, or AMA episode of the Drive podcast. I'm your host, Peter Attia. At the end of this short episode, I'll explain how you can access the AMA episodes in full, along with a ton of other membership benefits we've created. Or you can learn more now by going to peterattiamd.com forward slash subscribe. So without further delay, here's today's sneak peek of the Ask Me Anything episode.
Hey everyone, welcome to this week's episode of The Drive. Today is an AMA with Bob Kaplan. And in this episode, we go super deep on cancer screening. We've had so many questions about this, and we kind of lumped them all into one episode. So we get into kind of the what you need to understand cancer screening, sensitivity, specificity, positive, negative predictive value, all those things, and then kind of go through the different modalities, i.e. how you would actually go about doing these screens, and how you can improve their predictive value by stacking them on top of each other. So hopefully you enjoy this one and check it out. This is probably a really good one to check out on video because we use a lot of visuals, including a spreadsheet that you can manipulate to better understand the concepts.
So if you're a subscriber and you want to watch the full video of those podcasts, remember you'll want to see it on the show notes page. And if you're not a subscriber, you can at least watch the first part of this video on our YouTube page. So without further delay, please enjoy AMA number 25
Hey, Bob, that's a lot of books behind you, man. Have you read all of them or most of them?

**Bob Kaplan** (1:44)
Thanks for noticing, Peter. I'm a voracious reader.
Sometimes my appetite is too big. I have to admit, I haven't read all of them. Maybe 90%, I think at this point.

**Peter Attia** (1:53)
It's impressive. Everything, the classics, literature, science.

**Bob Kaplan** (1:57)
Mostly the classics. You can probably tell by the book binding on some of those.
Hard to get them out of the shelf, to be honest, to pull those things out. They're in there so tight. Yeah.

**Peter Attia** (2:07)
And it's good too. Your kids can do little projects, flattening leaves and stuff like that.

**Bob Kaplan** (2:11)
Yes.

**Peter Attia** (2:12)
We've got more of those going on.

**Bob Kaplan** (2:13)
Yes, it's fun for the whole family.

**Peter Attia** (2:15)
All right. Well, what do we have on the docket today for AMA number 20 something, 25?

**Bob Kaplan** (2:21)
25 In a similar vein as some of the previous AMAs, I consolidated a bunch of questions around a particular topic. And this one is cancer screening. We've gotten a bunch of different questions related to cancer and cancer screening. So you've got, I'll give you a flavor of some of the questions that we've received.
How do you think about cancer screening? Why and or when should I be screened? Which tests are worth getting?
What do you think of liquid biopsies?
How do you interpret sensitivity and specificity of tests? What do those actually mean? What are some screening tools for cancer you use in your practice? There's another one. I don't know if this was a question from someone, but I found this very interesting. And this question is, can you discuss how you categorize cancers and how you screen for each? So I remember you told me this too, and it was pretty interesting. I don't know if everybody would suspect this answer, but cancers outside the body versus cancers inside the body. So we'll get into that a little bit, but I think it probably makes sense to start off with sort of in general, I know you're a strategy person. I know you love tactics too.

**Peter Attia** (3:21)
Now, just to be clear, Bob, do we have three or four hours set aside for this podcast?

**Bob Kaplan** (3:29)
Hopefully, it's the latter. Yeah, I think this could be a long one.

**Peter Attia** (3:32)
Where would you like to begin?

**Bob Kaplan** (3:33)
I think we should begin from the top. The first question was, how do you think about cancer screening?

**Peter Attia** (3:38)
I guess putting this in the context of what we're interested in clinically probably sounds repetitive, but longevity has these two components and they're not independent, but sometimes it's helpful to think about them in isolation. Lifespan, health span. How do you live longer? And then how do you live better? In many ways, cancer versus the other major chronic diseases that rob a person of lifespan, namely the atherosclerotic diseases and the diseases of dementia and neurocognitive decline.