Morning Wire XX
[0] A growing body of research suggests that while cancer rates overall have been in decline in America, certain cancers among young Americans are on the rise.
[1] In this episode of Morning Wire, we speak to an expert about the troubling trends and who is at risk.
[2] I'm Georgia Howe with Daily Wire editor -in -chief John Bickley.
[3] It's Sunday, January 21st, and this is Morning Wire.
[4] Joining us today is John Hopkins Professor of Oncology and Epidemiology, Dr. Odis Brawley.
[5] Dr. Brawley, thank you so much for coming on.
[6] Oh, it's my pleasure.
[7] Now, in recent years, and just particularly in the past few weeks, this has been in the headlines, there's been some emerging research suggesting some concerning trends in cancer diagnoses in the U .S. Can you tell us what the research is saying and why doctors are concerned?
[8] Yeah.
[9] Well, there's good news and there's bad news.
[10] The really good news is there's about 33 % decline in age -adjusted mortality from cancer.
[11] since 1991.
[12] That means that your average person of, say, age 50, their risk of dying from cancer today or in their lifetime is two -thirds what it was for a person age 50 in 1990, 1991.
[13] So that's a good thing.
[14] We have a few cancers where the incidence is growing, especially the incidence or risk of being diagnosed before the age of 50.
[15] The one that everyone is talking about is colorectal cancer, but there's also some signals in pancreatic cancer as well as some other gastric cancers where it seems that people in their 30s and 40s are starting to get this more frequently than people in their 30s and 40s 20 or 30 years ago.
[16] The trends in colorectal cancer were first noticed about 15 years ago, and they've accelerated a little bit.
[17] that the trends in pancreatic cancer were first noticed, perhaps, about 20 years ago.
[18] Now, the trends upward in pancreatic cancer are not nearly as steep as the trends upward in colorectal cancer.
[19] And when you say not nearly as steep, how steep are we talking about when it comes to these colorectal cancer rates?
[20] The colorectal cancer rates have been going up by about 1, 1 .5 % per year.
[21] The increase is not increased.
[22] incredibly significant, but the story is this is starting to go up when everything else is going down.
[23] The number of young people, that is people under 50, who are being diagnosed with and dying from colorectal cancer, is still very low.
[24] Literally what I'm saying is 95 % of people who get colorectal cancer are still people who are over the age of 50.
[25] Now, both cancers you mentioned, mentioned are GI -related, and you said the trends were identified about 15 and 20 years ago.
[26] What are some suspected causes, and can we pinpoint any cultural and or environmental changes that might have contributed?
[27] It's likely that this increase, especially in colorectal cancer, is due to changes in diet that may have gone back to the mid -1950s, early 1960s, in the American population.
[28] And by the way, this is an increase that we're seeing in a couple of Western countries, especially Australia and the United States.
[29] Less so in Western Europe, but there is a small increase in Western Europe.
[30] It could be changes in diet that are causing it.
[31] In the United States, especially, we have had a terrible obesity epidemic.
[32] In 1970, for example, 5 % of our kids were obese.
[33] Today, it's well over 20 % of our kids are obese.
[34] 1970, 15 % of adults were obese.
[35] Today, it's getting close to 40 % of adults are obese.
[36] So we have this increasing obesity problem.
[37] We have an increase in really processed foods that we've seen.
[38] There may be a change in our gastrointestinal flora.
[39] Bacteria that are in our gut may be changing a little bit because we've had 50 to 60 years of incredible overuse of antibiotics to treat a myriad of different illnesses.
[40] And that can actually change the gut flora.
[41] That is the bacteria that are in our colon and GI system.
[42] And that may increase our risk of some of these cancers.
[43] Now that sort of preempts my next question.
[44] I understand there's a link between human papillomavirus and cervical cancer, is there any indication that some sort of microbe, viral, or otherwise could be implicated in some of these cancers?
[45] Well, by the way, the link between human papillomavirus is with head -neck cancer, especially tonsular and nasal pharyngeal cancer as well as cervical cancer and several other genital cancers.
[46] So it's not just cervical cancer.
[47] We already know that gastric cancer is linked to a bacterial infection called H. Pylori.
[48] That was a Nobel Prize from about 30 years ago.
[49] There very well may be other GI cancers that are linked to bacteria or viruses.
[50] That is for study, but not something that we definitely know right now.
[51] But there are some hypotheses out there that some of these cancers are due to changes in gut flora, which would mean changes primarily in bacteria.
[52] bacteria versus viruses.
[53] Now, just one more question on that note.
[54] I remember when I was a teen or early 20s, there was a big push for the Gardasil vaccine, and that's since become very mainstream.
[55] Has there been a decrease in cervical cancer since the implementation of that?
[56] Well, you know, it's interesting.
[57] There was a decrease in cervical cancer deaths that actually started back in the 1960s, and a major part of it was due to screening and treatment of several dysphysia or precancerous lesions.
[58] With the Garda Cell and other HPV vaccines, we've been vaccinating children to prevent a disease that typically occurs among women in their 40s and 50s.
[59] So the answer to your question is we've seen a small decrease that may be attributed to the vaccine, but we anticipate seeing a much bigger decrease within the next 10 to 20 years.
[60] We got to let those 10 -year -olds get into the 40 -50 -year -age range before we're actually going to see a large decrease.
[61] But there's some evidence of decrease already, especially in cervical dysplasia, which is not cancer.
[62] It's a pre -cancer, which left loan will oftentimes go to cancer.
[63] Now, what about some other environmental factors?
[64] I'm thinking specifically about chemical exposure or radiation.
[65] Past generations, for example, weren't in such close proximity to electronics all the time.
[66] We're also exposed to many more pharmaceuticals and starting at much younger ages.
[67] Well, first off, we know the cause of cancer in about 45 % of the population.
[68] And even now still, the most common cause of cancer, and it's like, linked to 18 different cancers is tobacco smoke, be it primary smoking or secondary smoking.
[69] The flight attendant studies in the 1970s told us that flight attendants who don't smoke are at higher risk of smoking -related cancers versus ticket takers at the airport who did not smoke.
[70] So we know secondhand smoke causes cancer.
[71] We know tobacco is the leading cause of cancer.
[72] Second leading cause of cancer, but within the next five to ten years, the leading cause of cancer is going to be a combination of consumption of too many calories, storage of too many calories.
[73] We call that obesity and not enough exercise.
[74] Think of it as a three -legged stool.
[75] The professional name is energy imbalance.
[76] Number three is going to be alcohol use.
[77] About one in 20 cancer, in the United States are linked to alcoholics.
[78] Then infections like HPV, hepatitis, HIV are all causes of cancer as well.
[79] So viral causes of cancer.
[80] Now, air pollution, exposure to certain chemicals are all clearly causes of some cancers.
[81] For example, lead exposure has been linked to cancer.
[82] But the biggies, the thing that causes more than a third of all cancers, are either linked to tobacco or energy imbalance.
[83] Now, you indicated that the prevalence is still quite low, but in recent years there have been some headlines about cancers being identified more frequently in young, very healthy, fit people.
[84] Perhaps it's still just a very small number and it remains small.
[85] But when it comes to that cohort, young, healthy, active, non -smokers, et cetera, are there any known risk factors?
[86] Yeah, having DNA.
[87] Oh, yeah.
[88] I mean, seriously, not to be facetious, about half of all cancers are purely due to the fact that people either have an inherited tendency to get to cancer or as we go through evolution.
[89] of cells turning over, more and more cells turning over, and, you know, we end up with mistakes in duplication of DNA.
[90] And some of those mistakes in duplication of DNA can cause disease.
[91] We call those mistakes mutations.
[92] This is actually the reason why you see more cancer and people who are in their 70s and 80s than you see among people in their 50s and 60s.
[93] The older you get, the more times you've gone through this cycle of DNA replication, and the more chance there is that you're going to have a mistake in that DNA replication leading to a tumor.
[94] Indeed, the reason why smokers get lung cancer is they end up with lots of inflammation, and a lot of their lung cells are going through even faster DNA replication as those cells are sloft off and dying and so far.
[95] And so they end up with an even greater chance of having these mutations.
[96] Now, something really interesting that I saw a lecture about recently is that doctors who treat certain common cancers will often see the same mutation repeating in different people, and it will create this sort of predictable disease course.
[97] That seems odd when mutations are supposedly random.
[98] So it seems strange that you'd have these common mutations that are causing common subtypes of cancer.
[99] Just the mathematical probability of the same mutation occurring frequently in different people seems unlikely.
[100] Is there a hypothesis about why we see these non -random mutations causing cancer?
[101] Well, two things.
[102] One, many mutations are inherited, especially mutations that cause many of the pediatric cancers or many of the cancer seen in adolescents and children.
[103] Many of them are inherited.
[104] Some of them are caused by environmental means.
[105] Now, when you look at DNA, DNA is frequently folded.
[106] If you look at the three -dimensionality of DNA, if you have an environmental hit on DNA, there's certain areas of the DNA that are more exposed and more likely to be damaged.
[107] And so this portends to, you're more likely to get specific types of mutations.
[108] It's really interesting.
[109] So thus far, we've mostly focused on adult cancers, but we have also seen an increase in childhood cancers.
[110] Specifically, I read that we have seen about a 30 % increase in leukemia since 1975.
[111] Has that been a slow and steady increase, or was there a certain time period where we saw a jump.
[112] What do we know about that?
[113] It is a slow and study increase.
[114] Now, the leukemias are perhaps more likely to be linked to some environmental causes, things that can disrupt DNA and that sort of thing.
[115] You know, we know that ionizing radiation increases risk of leukemia.
[116] By the way, one of the things that I did not mention as a cause of cancer, we now know that about 1 % of all cancers are caused by medical radiation.
[117] And so we actually worry about exposure to CT scanning and x -rays and nuclear medicine tests, especially among children and among younger people.
[118] By the way, the younger you are when exposed to radiation, the more likely that radiation is to ultimately cause a cancer to erupt because the younger person has a longer runway who's going to end up going through more of those mitotic cycles that we were talking about.
[119] Now, there are some cancers where a diagnosis at a younger age is more concerning for prognosis.
[120] I'm thinking specifically of breast cancer and young women.
[121] When it comes to this cohort of younger people getting cancer, are these cancers generally more aggressive?
[122] And if so, do we have good treatments?
[123] Some are and some are not.
[124] In the case of colon cancer, some of the colon cancers, especially those that are familial and genetically predisposed.
[125] Those cancers are actually frequently less aggressive.
[126] It's a spectrum.
[127] Most of these cancers, we worry about the fact that you've got someone who is young, say, 40 years old.
[128] Therefore, we're worried about trying to keep this thing from coming back or keep this thing from being a problem over the next 40 or 50 years and a 40 -year -old.
[129] And so you do have to worry about that.
[130] Some of them are going to be more treatable, usually the more familial ones that are inherited through families.
[131] The ones that are not familial, we tend to treat very much like older people with cancers, and they have similar prognosis over the same time frame, over the 10, 20 -year horizon.
[132] All right.
[133] Well, we're just about out of time, but Dr. Brawley, thank you so much for coming on today.
[134] My pleasure.
[135] It was fun to talk to you.
[136] I appreciate your efforts to try to educate folks.
[137] That was Johns Hopkins oncologist and epidemiologist, Dr. Otis Brawley.
[138] And this has been a Sunday edition of Morning Wire.