'In Good Health': Why Is Colorectal Cancer Affecting Generations Differently?

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0:24Colorectal cancer cases in young people have risen nearly 60 percent since the early 2000s. That's according to data from the CDC and the National Cancer Institute. A new study out this month by the American Cancer Society underscores this rise, finding that colorectal cancer is now the deadliest cancer for those younger than 50. But the rise is generational. People born around 1990 are four times as likely to develop rectal cancer than those born around 1950. And for those 65 and older, colorectal cancers have actually been decreasing. I'm Jen White. You're listening to the 1A Podcast. Today, for our latest installment of In Good Health, we ask, what's going on?

1:07And what can we do to protect ourselves and our gut health? We'll get to those questions and more after this short break. Stay with us.

1:17This message comes from Stamps.com. Shipping, billing, admin, you're managing all these things. Why waste time sending important documents the old-fashioned way? Mail and ship when you want with Stamps.com. Print postage on demand and schedule pickups from your office or home. That's why over 1 million small businesses trust Stamps.com. Go to Stamps.com and use code NPR to try Stamps.com risk-free for 60 days. Welcome back to the 1A Podcast. Let's get into our conversation about colorectal cancer and meet our panel of experts. Dr. Jeffrey Meyerhardt is a gastrointestinal medical oncologist. He's also the co-director of the Colon and Rectal Cancer Center and the chief clinical research officer at the Dana-Farber Cancer Institute in Boston.

2:04Dr. Meyerhardt, welcome to the program. Thanks for having me, Jen. Also with us, Dr. Mark Pochapin. He's the division chief of gastroenterology and hepatology at NYU Langen Health. He's also a host on SiriusXM's Dr. Radio. Dr. Pochapin, thanks for joining us. It's so great to be here. Thanks for having me. And also with us, Rebecca Siegel. She's an epidemiologist and senior director of cancer surveillance research at the American Cancer Society. Rebecca, welcome back. Thank you so much. Very happy to be with you. And to know that the information given here is not medical advice, it's not a replacement for your own physician.

2:42Rebecca, let's start with this analysis that came out this month. You're the lead author on it, and it's about the rates of colorectal cancer in young people. Talk us through these rising numbers we're seeing. Yes. So it's quite shocking how the landscape of colorectal cancer is changing, how rapidly it's changing. And this report actually looked at colorectal cancer overall in the United States. And even though incidence and mortality are continuing to decline overall, those rates are, that trend is really driven by the oldest adults, 65 and older. And in that age group, rates are decreasing by more than 2 % per year.

3:27But we're increasingly seeing a younger age at diagnosis so that people under 50 have an increase of about 3 % per year. And even people in middle age, 50 to 64, have an increase in incidence of 0.4 % per year, which seems really small and maybe not important. But the surprising thing about that is that 66 % of those folks are being screened for colorectal cancer. So it's really surprising that we can see any increase at all because colorectal cancer screening typically prevents cancer. And the other thing that makes that surprising is that rates were decreasing at the same magnitude that they are in older adults prior to the increase.

4:18And so it's because of what we call a birth cohort effect that we can describe later. What was your initial reaction to what you found as you were analyzing this data? I was very surprised because we actually are reporting an increase in rectal cancer incidents across the board for all ages combined for the first time since cancer rates have been recorded. So previously, rectal cancer incidents had been declining. I think part of that is because we've long been able to do rectal exams because we're only talking about six inches in. And so rates have been declining for many, many decades. But now we're seeing an increase in rectal cancer.

5:08And the reason is because this increase in incidence is primarily confined to cancers in the rectum and the sigmoid colon, which is that part of the colon that's right next to the rectum. So we're talking about the very end of the large intestine. Dr. Porteapin, what was your initial reaction when you learned about these rising rates, especially among younger cohorts? Well, although it's alarming, I think in the gastrointestinal world, we're not surprised because we've been seeing it clinically. We're seeing younger adults present with rectal bleeding, as Rebecca mentioned, because the cancer is lower in the colon, it often presents with either blood loss or bleeding.

5:52So we've been seeing it. And actually, we've seen a rise over the past 10 plus years. But what's so alarming is the continued rise and the rate of rise, especially when And the rest of this story is such a public health success story of increased screening and older adults dropping both in incidence and mortality. But it's alarming. I think we do have to make sure that people understand, particularly younger patients, but everyone, if they see rectal bleeding, they can't just write it off as hemorrhoids or something that will go away. It needs to be evaluated. And I think in the medical community, what Rebecca is talking about is something that we need to apply clinically, meaning that if someone presents with rectal blini and they're young, you need to evaluate it almost certainly with a colonoscopy to make sure that there's nothing going on that might be missed.

6:44What unfortunately happens is, and we have data to support this, that younger people are delayed in their diagnosis because very often either they don't present or it's written off as something that's really minor, like a hemorrhoid, which it certainly could be. We don't want to create panic. But the point is that it can't be ignored. It needs to be addressed by someone who will take it very seriously and make sure we rule out the more concerning conditions. Dr. Meyerhard, when you hear this data, how different is your understanding of this disease and who it affects from, say, 20 years ago? Yeah, no, and I absolutely agree with the comments so far.

7:21I mean, we are also seeing, I work in a dedicated cancer center. We have always seen younger people overall with disease because often they'll come to us into the city or a dedicated cancer center, but we definitely have many more patients that are under the age of 50 that we're seeing. And these data now have had some awareness for over a decade, but we're still seeing every year, and there's been a lot of stories about that, and every year we're still seeing an increase, which is concerning, because we're hoping, obviously, with all the coverage that's being done, including in this program, to have people aware that if they have symptoms, particularly bleeding or other bowel symptoms, to really bring that to the attention of their physician.

8:06But the delay of diagnosis is real. We'll see people at a later stage, more patients at a stage, unfortunately, that's often not curable or a later stage with a higher risk of recurrence. And that is still alarming. Well, we're hearing from many of you. A member of our tax club writes, My mom died of colorectal cancer at 46. We have a genetic family link. Thank goodness we all get tested early and often. And another of you shared this. My brother died of colon cancer at 48. He had symptoms for four years but did not have insurance, and he never shared his concerns with our family. We lost him over a period of 10 months from time of diagnosis.

8:44It is an insidious disease. I wish they had started urging family members of people with polyps to start getting tested at 40. It may have saved his life. Losing him was the worst thing that has ever happened to our family. Dr. Meyerhardt, for the younger generation who's now more likely to be diagnosed with colorectal cancer, What are some of the unique challenges this age group faces when diagnosed, including things like sexual health, fertility, or even access to health care? Yeah, I mean, I think it's all of what you just said. I mean, these, you know, being diagnosed in your, it depends on your decades.

9:21So being diagnosed in your 20s, you know, some of them are still in schooling. They're just finishing schooling and starting a career. They're starting potentially a family. And there's all those issues related to trying to get treatment, trying to work, trying to create those social connections and establish yourself in a community. Same with the people in their 30s. They just have different considerations. They have parents that they're also helping to take care of. So there's a lot of different challenges that, depending on the decade of life that you're getting treated, that have to be accounted for.

9:57And health insurance is also a real thing. As, you know, once patients are off past age 25, they're off of their potential family's health insurance and they're on their own. Depending on their job depends on the insurance product they pick, which could have a high burden in terms of co-pays and deductibles and obligations that they have too. And getting treated for cancer is expensive. And these are considerations in how they do overall planning. We have lots more to discuss, but before we go any further, Dr. Pochapin, what are the symptoms of colorectal cancer people should look out for? You mentioned bleeding, but what are some of the other signs that may not be as obvious that there could be an issue?

10:44And Jen, thank you for bringing up symptoms. I want to first just make the distinction between symptoms and screening. And we talk about screening, starting everybody at age 45 or younger, 40 or younger, depending on what the family history is. You mentioned some of these really upsetting phone calls and emails that you get about people who have younger onset. Knowing your family history is critically important, starting 10 years before the onset of the youngest person in the family. But that's screening. That's a healthy person who has no symptoms. What you're asking about is what are the presenting signs or symptoms of someone with colorectal cancer.

11:21We mentioned rectal bleeding, unexplained anemia, particularly iron deficiency anemia. Now, a lot of young women do have iron deficiency anemia because of menses and not repleting the iron. However, if there is new iron deficiency anemia, that should be investigated. a change in bowel habits and frequency, and not just once or twice, but an ongoing change. New constipation, thinning of the stools, where the stool looks a little bit more like a pencil, that it's being extruded through something more narrow, more difficulty passing the bowel movements. Again, these things can happen. Everybody develops intermittent constipation.

11:59If it's consistent and persistent, it needs to be evaluated. Let's take a quick break here. coming up, why we might be seeing this rising rate of colorectal cancer, and when you should talk to your doctor about getting a colonoscopy. We'll be right back.

12:17This message comes from Babbel. Babbel's conversation-based language technique teaches you useful words and phrases to get you speaking quickly about the things you actually talk about in the real world. With lessons handcrafted by over 200 language experts and voiced by real native speakers, Start speaking with Babbel today. Get up to 55 % off your Babbel subscription right now at babbel.com slash NPR, spelled B-A-B-B-E-L dot com slash NPR. Rules and restrictions may apply. Let's get back into our conversation about the rise of colorectal cancers in young people. Steve writes in to say, you mentioned the risk for those born around 1990 and those 65 plus.

13:01Can we infer a risk somewhere between those groups for 45-year-olds, or is it more complicated than that? Rebecca, I'll come to you. Sure. So I referenced before the birth cohort effect, and it's actually the most important message of this research because what it means is that people who are born after 1950 have higher risk. Every generation born after 1950 has a little bit higher risk than the generation before. And that's the reason that we're seeing an increase now in middle-aged people, because those who are on the beginning of that wave of higher risk, like me, I was born in the 1960s, I've aged into middle age.

13:50And so we're bringing that higher risk with us into middle age. And what that tells us is that the increase in young adults is a canary in the coal mine for the future burden of colorectal cancer until we understand what's causing this increase and are able to intervene. So that's very concerning and just something really important I want people to understand. This is not an early onset problem. Now we're seeing an increase in death rates in people 50 to 64, again, who have a pretty high level of screening. And so research is key to understanding what's causing this. But very important idea to understand.

14:37We got this message from another member of the tax club. My son-in-law's father was the CEO of a publicly traded company at the age of 47 and died of colorectal cancer at 50. His loss illustrates that cancer strikes without regard to age, economic status, or education. Rebecca, in this research, were there any other cohorts that had higher rates of colorectal cancer? Did you control for sex? Did you control for race or economic status? In this particular study, we haven't, but we've done a lot of research over the past 15, 20 years on this topic. So we've been following this. And what we're seeing is that the steepest increase, first of all, rates are increasing across race and ethnicity, across socioeconomic status, and across the country.

15:33And in fact, this is also happening in many countries in the world now, mostly high-income countries, but not all. and but what we are seeing that's extremely concerning is that American Indian and Alaska Native people have the steepest increase of early onset disease which is only exacerbating their already high burden they have the highest incidence of mortality in the country and in fact Alaska Native people have the highest incidence of mortality in the world for reasons that aren't aren't well understood. And so there are differences in the burden, but the increase in disease is happening across populations.

16:19Well, another member of the tax club writes this, two people close to me have experienced this. One was just 30, the other more recently, a male aged 45. Early detection is what saved their lives, and there's just no underestimating the importance of colonoscopies. Dr. Meyerhardt, in 2021, guidelines lowered the age recommended for colonoscopies from 50 to 45. We talked earlier about some of the symptoms people should look out for, including blood in the stool, changes in bowel habits. When should people be screened for colorectal cancer? Yeah, so as you said, the screening for the general population was changed to age 45.

17:00To bring up, again, there are a percentage, up to 15%, 20 % of patients diagnosed with colorectal cancer have a family history. And that could come in two forms. It could be either something that's been genetically passed on over generations, or it could just be a family history that we don't know specifically the gene. And that does affect when you think about initially screening. So the general guidelines, if someone has a family history that's not considered a germline, something that's passed on from generations, is to be 10 years prior to the diagnosis. One of your earlier viewer questions brought up the issue that they had a family member who had a polyp.

17:43And I would also want to emphasize polyps. Most colorectal cancers start as polyps. And if you remove a polyp, it prevents a cancer. So knowing your family history of family members who's also had polyps is important because that also should be considered if your dad had a colonoscopy at age 48 and had some polyps, you should have an initial colonoscopy in your mid to late 30s because, again, that could have become a cancer. So family history is an important consideration thinking of initial age. for those who don't have a family history. Again, the guidelines right now are to start at age 45, but as we're seeing from the statistics, particularly where there's even a higher increase rate in the 20s and 30s, is trying to figure out who are the patients who are potentially higher risk.

18:37Because it's probably not realistic that we can screen everyone starting at age 20 with the current screening techniques and potential risks of also screening screening that are small, but there if you do in a very large population. So trying to understand who are the ones who are higher risk in their 20s and 30s and 40s, I think really will help with earlier detection in the right populations. Dr. Perchapin, when we talk about polyps that may be found during a colonoscopy, just sort of connect the dots for us. How and when does a polyp actually develop into cancer. Thanks, Jen. This is a very important point because colon cancer is actually one of the most preventable of cancers.

19:23The other one, I would say, would be cervical through pap smear. But other cancers, when we do screening for, we're actually looking for an early cancer when it's highly curable. And that's true with colon cancer as well. But we're trying to prevent the disease. And that's how colonoscopy is so powerful, by finding these polyps. Now, we believe most cancers that we heard comes from polyps, but not all polyps turn cancerous. Yet, if we find polyps and remove them, we prevent every one of those polyps from ever having the opportunity to turn cancerous. And it takes years for that process to happen, 10, 15 plus years.

19:57And so, we have a real big window of opportunity, and that's why generally we screen every 10 years, starting at age 45, the next would be 55 if no polyps are found. finding the polyp and removing it prevents it from ever having the opportunity. And even though not many polyps will turn cancerous, by removing all the polyps, we hopefully prevent almost all of the cancers through the screening. So that's why knowing your family history and getting started at the right time is so important because starting younger, and we did a study on this actually, and we looked at a database and we found that younger people below the age of 40 even have a high percentage of polyps.

20:36So we're seeing not only more cancers, but more of these polyps. And that's why if someone has a family history where someone had larger or multiple polyps, they should get screened younger as well as if the family had a family history of colon cancer. Well, we got this email from Matthew in Cincinnati who says, what do researchers and doctors think is causing the increased rate of colorectal cancer in young adults? Is it diet, lifestyle, use of controlled substances? We've had some people ask about sexual habits. Rebecca, how much do we know about what might be causing this increase, not just in colorectal cancer, but as we just heard there from Dr.

21:14Pochapin, also an increase in just the number of polyps they're finding? Sure. So that's a great question. We actually know a lot about what causes colorectal cancer in general. and about half of colorectal cancers are attributed to these risk factors. But the problem is that these risk factors were established based on older adults who have different exposures than the people, than the generations that we're talking about now who have increased risk. So studies, there have been a few studies that have looked at younger adults, but it's very difficult because, again, most established cohorts are older individuals because this is so unusual.

22:04Cancer doesn't usually happen in people under 50, particularly colorectal cancer. And so there has been a few studies. One study attributed about 20 % of the current increase in risk to excess body weight, Probably sedentary activity is also contributing. But interestingly, especially because of where these cancers are occurring, the established risk factors don't seem to at least completely explain this increase. And here's a quick example. Physical inactivity, it's very strongly associated with colon cancer risk. And we know this from older adults. So this is a very established risk factor. But interestingly, it's specifically associated with cancers in the colon, and there doesn't seem to be an association with cancer in the rectum, which is what's driving this increase.

23:09And so that's why we think it's probably a newer exposure. And the birth cohort effect tells us the timing of this exposure Because again, we're seeing an increase in generations born after 1950. So this tells us that some change in behavior or exposure was introduced around the middle of the 20th century. That's increasing our risk of colorectal cancer. And there's a lot of studies ongoing around the world looking at things from antibiotic use, high antibiotic use in young children, as well as processed foods. We know already that processed meat is classified as a carcinogen because of its association with colorectal cancer.

24:02So ultra-processed foods are also something of interest as well as microplastics. So a lot of this research is ongoing, but it will take time. We are getting lots of questions about the ability to screen for colorectal cancer at home, specifically about the Cologuard at home test. Dr. Meyerhardt, what can you tell us about the use of that test as a way to screen at home, especially before you may qualify for a colonoscopy? yeah so what we know is there are actually multiple techniques that are that can be used to screen for colorectal cancer and each of them have advantages and disadvantages in different what we call sensitivity ability to detect disease if it's there and specificity you know knowing if the disease is there, if it's going to be positive or negative.

25:05And you want to avoid false negatives as well as try to reduce false positives because that would lead to additional testing. The simplest is sending home stool cards that you collect some stool and essentially looking for blood in the stool. And that actually is where there's the most and largest data from very large studies that have actually shown a decrease in colorectal cancer incidence and mortality. It is also the least sensitive. And it's not as sensitive to detect polyps, which, as was discussed earlier, are really what we want to find in patients. Um, colonoscopy is, is still considered the gold standard where you could visualize, um, the entire colon and again, act if you see something that's of concern, either a polyp or, or some, uh, patch that looks like it needs to be biopsied to make sure there's not changes in the cells.

26:07Um, in between is, is, is other techniques. There's a CT way to kind of look inside the colon, but that, again, has to be followed for colonoscopy if they find anything abnormal. And better than just looking for blood in the stool are various DNA tests, ColoGuard being one of them, which has had increasing data in terms of sensitivity and relative ease for patients because they can do it at home and send it back. And then, again, it needs to be followed up with a colonoscopy. And it does also have a lower sensitivity for polyps relatively compared to a colonoscopy. But I think the key message that most of us want to give is that some type of screening is certainly better than not doing screening at all.

26:59And the more sensitive the test is probably better. And each of the tests have different cadence or frequency that you have to do depending on the results of that test. So I think stool tests at home are important because they could be given a wider population. They all will need to be followed up to the abnormal. But again, the importance is to do some type of screening. We got this email from Barbara who says, My daughter was one who died before 50 of colon cancer. I've heard of a possible connection with gut biome. She had rheumatic fever as a child and took an antibiotic daily for over a decade, as was recommended at the time.

27:37Has this been looked into? Now, we did hear some reference from you, Rebecca, about antibiotics. But what more can you tell us about what's being the possible connections between the health of the gut biome and colorectal cancer? Yes. The gut microbiome is a large area of interest. And of course, we're talking about many exposures that can influence this microbiome. There are good bacteria and harmful bacteria, and the balance of those is key. So there's, I would say, in terms of the research on antibiotic use, there's some evidence, but certainly not definitive. And so there is more work to do on all of these exposures.

28:31Still to come, how to keep your gut healthy and we answer more of your questions. That's just ahead.