Breaking Down Cancer Prevention: What Really Works?

In this episode of Breaking Down Health Care, John Hennessy and Dr. Michael Kolodziej explore the crucial difference between cancer screening and true cancer prevention, highlighting how lifestyle changes, vaccines, and emerging therapies like GLP-1s could meaningfully reduce cancer risk on a population level.

John Hennessy, MBA: Hi, I am John Hennessy. I'm here again with my colleague, Mike Kolodziej. We're here Breaking Down Health Care yet again. Mike, today we're going to talk about cancer prevention, and maybe the best place to start is that cancer prevention and cancer screening aren't the same thing. How do we separate those two as we start a discussion about prevention?

Michael Kolodziej, MD: The philosophy behind cancer screening is to identify cancers at an early stage—to shift the stage to allow a better outcome, a cure. Mammography, colonoscopy, cervical cancer screening, and lung cancer screening all have the same goal: let's find that cancer early, before it gets big and bad, and keep it from spreading elsewhere.

Cancer prevention is altogether different. Cancer prevention is an attempt to keep cancer from developing in the first place. Now, the truth of the matter is that both have the same ultimate goal, which is to reduce death from cancer. But cancer prevention is really designed to keep cancer from occurring in the first place.

Hennessy: When we think about prevention, it's not a 1 or 0; it's a relative risk reduction. We have these studies that come out and talk about the reduced risk of death. I'm pretty sure death is undefeated. How do we think about relative risk reduction? Maybe the second part of that question is, how do you talk to patients about that?

Dr Kolodziej: I would agree that we generally do not have any strategy that 100% eliminates the risk of developing cancer. Because cancer isn't one disease and because every cancer has a different pathophysiology, it's very hard to develop a single strategy for cancer prevention.

How do you talk to patients about it? Actually, oncologists already get the horse when he is out of the barn, so to speak. I think cancer prevention is a primary care task. When we think about the kind of things that we can adopt in terms of, for example, lifestyle choices to reduce our cancer risk, that's the primary care doctor's domain.

You identified a problem, which is relative risk reduction as opposed to absolute risk reduction, and how to maintain some sort of credibility when you're telling a patient that if you lose weight, you'll have a lower risk of cancer. That's a true statement, but it's a relative risk reduction.

If you stop smoking, you will have a lower risk of lung cancer. That doesn't mean you'll have 0 risk of lung cancer, just like every person who smokes doesn't get cancer. There are other factors in play, but I think a lot of times when you talk to a patient, their response will be, "But I know somebody who did that strategy, and they still got cancer anyway. Why bother?"

It's hard to lose weight; it's hard to stop smoking. There are other cancer prevention strategies that aren't nearly as hard, that are quite effective. In the post, I discuss the hepatitis B vaccination, and I discuss the HPV vaccination. Those are great stories of ways that we can lower our our risk of getting cancer.

The story about hepatitis B and how it infects people, and sometimes it causes acute hepatitis, sometimes it causes cirrhosis, and sometimes it causes cancer. There is a similar story for human papillomavirus, and that also won a Nobel Prize.

I think there are things we can do that are really effective and safe, as best we can tell.

Hennessy: You said this is the domain of primary care, but I recall from running an oncology practice that when we had patients who had a primary cancer, we talked to them about, "Hey, you still have to do your colon cancer screening even though we've been treating you for breast cancer."

Would you say the same thing is true for patients who've not had these vaccines? Or is it simply too late for some folks?

Dr Kolodziej: For HPV, it's mostly too late. For hepatitis B, there's still some benefit. But the classic example I used to tell my patients who had lung cancer is, “It's never too late to stop smoking.” It's just never too late to stop smoking.

It takes a while for the body to forget that you were a smoker. But cigarette smoking is associated with so many malignancies—bladder cancer, pancreas cancer, head and neck cancer. There are a million cancers that cigarette smoking is associated with, so if you stop smoking, you can do yourself a favor because, as we know very well, lung cancer survivors have a very high risk of getting a second cancer during the course of their lifetime. So there's always some benefit.

Hennessy: That's a really good point. I also think of transplant patients, multiple myeloma and others, who had been in a curative setting. It doesn't keep them from getting yet another cancer down the road.

When we think about these prevention measures, one of the challenges is getting people engaged in them. There are people reaching out to employers, Medicare advantage plans, and others to monetize these prevention measures. Is this something that's possible to do on a population basis? Or is this really a physician-patient convershangeation, or maybe even one involving folks other than physicians, given some of the trust issues we're dealing with these days?

Dr Kolodziej: Cigarette smoking is the best example. All health care providers can contribute to the dialogue regarding cigarette smoking. I used to quote a study that asked patients why they didn't stop, and many of them said, "My doctor never told me to." That should never be the answer. Of course, smoking cessation is a quality measure that gets rewarded and rewards payers, for example, via Stars. Cigarette smoking is an easy one.

Weight reduction is going to be the single most interesting opportunity for cancer reduction that we are going to see in our lifetime because there's preliminary evidence that the GLP-1s may reduce the risk of cancer. You don't have to lose a lot of weight. If you lose 5% to 10% of body weight, you do see a reduction in cancer risk.

We'll see about health plan coverage. Both Medicare—which to this day is unable to pay for any medicine that solely causes weight reduction (they can pay for it if it's for diabetes, for example, and weight reduction is a beneficial effect)—and commercial health plans, because, as we've read in the newspaper recently, we are going to see a substantial decline in the cost of GLP-1s. If that decline in GLP-1s opens the door for broader access and we see more weight reduction, the question is, will we see, in a decade, a significant drop in breast cancer, which is clearly related to weight, or colon cancer, which is clearly related to weight?

Will we see those drop off in the same way that we saw the cigarette cessation movement, which started with the surgeon general's report in the early 1960s and then the ban on tobacco advertising on television that led to a drastic drop in cigarette smoking in the US? This was followed, of course, by a drastic drop in lung cancer deaths in the US. That could be the great cancer story of our lifetime.

Hennessy: One of the challenges when you talk about this is the persistency of these efforts. I recall back to when I was running an oncology practice, and we had people who smoked who worked at the practice.

It was a real challenge for us because it's not great to have your front entrance filled with cigarette receptacles. But what we did was we paid for unlimited attempts because we thought it was just that important. Our health plan didn't, but the practice did, as an employer.

When you think about the time it takes to see the value of these prevention measures, is there a challenge in the way we finance health care on a 12-month period—that the people paying for this aren't going to see the value of it and may choose not to invest as they should?

Dr Kolodziej: There is little doubt that smoking cessation efforts don't cost very much money. In fact, in the short term, marrying smoking cessation with improved performance of lung cancer screening works well. Those two are so beautifully complementary in terms of reducing burden of illness and cost of advanced disease that we should be embracing both of those with open arms. GLP-1s have been difficult to talk about because of the cost. But there recently has also been some publicity regarding longer-acting GLP-1s with more favorable side effect profile so that you can get persistence on the GLP-1s, which seems to be very important.

I'll tell you, we started with the discussion of the distinction between prevention and screening, but they are, in fact, two of our most important tools on a population level to improve outcomes of patients with cancer.

Hennessy: When you think about this, and I'm thinking particularly about the GLP-1s, are we measuring this the right way? Is it possible to figure out if someone's cancer didn't happen because they were on a GLP-1 or not?

Should we be thinking about ways to measure it, or is it just going to be common sense that you're going to see a decrease in cancers and that was really the biggest lever that was pushed?

Dr Kolodziej: It goes without saying that we'll never have a randomized trial that’s GLP-1 versus no GLP-1 in terms of cancer risk. I think the best we're going to do are population level observation studies with some goal of showing a correlation between amount of weight loss and cancer incidence.

These studies are going to be possible because so many people will be on them. Of course, there will be people who don't take them for one reason or another, and we'll be able to see what happens to their weight and their cancer frequency.

We can look at very common cancers. Breast cancer and colon cancer are very common weight-associated malignancies. We don't need to look for cancer survival. I would argue it would be a mistake to hold out for survival. I think if we can prove you get less cancer, that's good enough because the GLP-1s have other beneficial health effects over and above whatever added benefit we see from cancer reduction.

Hennessy: The last thought here is we're starting to see some questioning or looking at data for cancer screening, in part because, while we certainly are finding cancers early, we're also having false positives, and there are some real logistical clinical costs to that. But it sure seems like with cancer prevention, the things you've talked about, there doesn't seem to be a real downside to this. It's all upside.

There may be some loss of pleasure from smoking or something like that, but it's not like if this doesn't work out, you're headed to a surgery you don't need.

Dr Kolodziej: That's true. There is one risk and that is complacency. If we make it sound too easy, then people won't do the other things they need to do to have a healthy life. We're at the infancy of this stuff. One thing we can say definitively at this point is that an attempt to take a pill like beta carotene or some other antioxidant to reduce cancer has never really proven to be of benefit.

If you think, "I'm waiting till I can go to GNC and I can get the pill that I need to keep my cancer away," don't do that. There have been so many studies, and there is no consistent statement that can be made regarding the use of any particular supplement to reduce your cancer risk.

Hennessy: Thanks everybody for joining us this afternoon. It looks like it might be raining where you are, Mike. We'll be back again to talk about oncology cancer care in the near future, so come back and join us. Thanks.

Dr Kolodziej: Thank you.