Cancer prevention – today and tomorrow
Most of us know someone who’s had cancer, and we’re surrounded by news stories about cancer’s causes and effects. But what about trying to prevent cancer in the first place? Oncologist Larry Gluck, MD, and LeAnn Perkins, a family nurse practitioner in oncology, survivorship and cancer, discuss what we can do to prevent cancer, as well as some breakthroughs that may be on the horizon.
Joey Wahler (Host): We hear so much about cancer. Most of us at least, know someone that’s had it, and we’re surrounded by news stories about cancer’s causes and effects. But what about trying to prevent cancer in the first place? We’re discussing cancer prevention today and tomorrow. Welcome to Flourish. A podcast brought to you by Prisma Health.
Thanks for joining us. I’m Joey Wahler. Our guests from Prisma Health are Dr. Larry Gluck, Medical and Hematology Oncologist and LeAnn Perkins, a Family Nurse Practitioner in Oncology, Survivorship and Cancer Prevention. Thanks to both of you for being with us. Before discussing specifics, I’ll ask each of you starting with you, Dr. Gluck, in a nutshell, what do we mean by cancer prevention?
Larry Gluck, MD (Guest): So, when we use the term cancer prevention, we are referring to any activity that can be initiated to actually decrease the risks of ever developing cancer in the first place.
Host: And you LeAnn?
LeAnn Perkins, NP (Guest): Yes, cancer prevention is actually any action taken to lower the chance of getting cancer. And there are primary and secondary prevention techniques.
Host: And I was going to ask you about that as well. So, you led me into it perfectly, LeAnn. What’s the difference between primary and secondary techniques for cancer prevention?
LeAnn: Primary prevention is anything that we do that hopefully reduces our risk of getting cancer in the future. So, this includes healthy choices, such as maintaining a healthy weight or a healthy body mass index, eating a healthy diet, exercising and avoiding substances such as alcohol and tobacco, and also too much sun exposure. And secondary prevention is actually when we use screening exams or tests to look for cancer in a person before they actually have any symptoms of cancer. So, these mostly are known to people as mammograms for breast cancer, PAP test looking for cervical cancer and then there’s colorectal cancer screening. And in addition, for people who are at high or increased risk of developing lung cancer, we have low dose CT scans looking for lung cancer in people, again, before they have symptoms.
Host: So, you’re really talking there about, on the one hand, people doing things they can take hold of. And on the other hand, having things checked they may not be aware of. So, Dr. Gluck, LeAnn hit on some of them there. Tell us a little bit more, if you would, about some contributing factors to developing cancer, that people can take control of themselves in their own lives.
Dr. Gluck: Yes, the last 20 to 30 years have been good to us. Prior to that, we understood that tobacco smoke posed a risk and perhaps some environmental things, but didn’t really have a lot of other insight as to what we could do for preventing those high risk issues. So, now we look at it and we say we have a much broader view.
So, contributing factors to cancer include obesity or excess weight as it changes the hormonal infrastructure in our body. A variety of dietary factors which we’ll elaborate a little bit further in the, in the podcast, lack of exercise. So, a sedentary lifestyle predisposes to colon cancer, breast cancer, prostate, and others. We have an increase in awareness of alcohol intake in that the breakdown of alcohol to include acetaldehyde can directly damage our DNA. Tobacco smoke with a variety of carcinogens, a family history, even if we can’t pinpoint a specific inheritance pattern, genetically, is of importance.
Certainly the genetic mutations probably comprise about five to 10% of the predisposition to cancer. And we now recognize more than 50 hereditary cancer syndromes. Infectious diseases, viruses, bacteria, and parasites. And then a variety of forms of radiation, be it sunlight, be it ionizing radiation, and so forth.
Host: I want to ask you more about diet as you touched on there, in a moment, but you mentioned something that I first want to follow up on, which is getting checked for genetic testing and family history, because that can play so much into this. Do people do that enough?
Dr. Gluck: So, I think it is under subscribed. Part of that is the fact that the field is changing very quickly. Many of the practitioners who are seeing patients on a regular basis had very little in terms of training in genetics, shed alone, applied medical genetics. But it indeed is a fast moving part of our strategy for prevention. And I think it will play a greater role as awareness is increased.
Host: So moving on to diet, LeAnn, for you. So much of our health is of course, related to what we eat. So, first in general terms, what diet recommendations can help prevent cancer?
LeAnn: Yeah, a diet that is rich in whole grains, lots of vegetables and fruits and beans. So, we really talk about a plant focused diet. The American Institute for Cancer Research and also Lifestyle Medicine have great websites addressing plant focused diets. So, someone may not be completely plant-based, but, and they can certainly limit their consumption of red and processed meats to help decrease the risk of colon cancer and other cancers, and also limiting the consumption of fast foods or other processed foods that are just high in fat and starches and sugar, and also limiting the consumption of sugary sweetened beverages.
We do have a lot of people in our Cancer Prevention Program that do ask about sugar. And how does sugar contribute to cancer? A lot of people have heard that and I would actually like Dr. Gluck to even talk about sugar, just for a second.
Dr. Gluck: Sure. The, this is a question that’s posed fairly commonly of is sugar a direct carcinogen? That is to say, can it cause cancer? The long established view was excess sugars, particularly the fructose products will contribute to the obesity epidemic and indirectly increase one’s risk of developing cancer. Over the last couple of years, there has been some fascinating research conducted that now shows in some of our animal models, that excess sugar is converted into what we call intermediate metabolites and that one of these, a dye fructose can actually activate a cancer gene. So, more to come about that. But I think we need to keep an open mind that cancer may be a multi edged sword. We have to bear in mind that sugar may be a multi edge sword.
Host: And Dr. Gluck to follow up from a couple of moments ago, how about the cancer risks associated with red and processed meat?
Dr. Gluck: Right. This is also a common question for us. But it’s also a common source of amazement when we present the data around both processed meats and red meat. So, what is the concern? Well, first of all, processed meats are those that have been transformed, generally for preservation and that could be by salting or curing with nitrites and nitrates, fermenting or smoking the product. And so, the hotdogs, the hams, the sausages and so forth, are all examples of processed meats. These are now listed by multiple international agencies as group one carcinogens. And that is that these are overtly cancer causing. And we now know that at least one way that they cause cancer is that the nitrates and the nitrites can create what are called nitrosamines and these molecules can directly attack and change our DNA. So, it’s a chemical modification called alkylation. Red meats that have not undergone the processing that I’ve just mentioned are now listed as likely carcinogenic. That’s called group 2A and that’s because mammalian meat, so this is muscles of mammals. So, these would include veal, pork, lamb, mutton, et cetera, that the breakdown products of the heme iron also contributes to nitrosamines, which again, can directly chemically alter our DNA.
Host: Interesting. A lot to take in there, certainly for people to consider concerning their diet. Switching gears, LeAnn, we’re immersed of course, in vaccine info these days, but for the purposes of this conversation about cancer prevention, are there any vaccines that help to do that.
LeAnn: Yes, there definitely are. So, primary prevention also includes vaccines. So, these would be especially hepatitis B vaccination, which was actually approved in 1981 began given to infants in 1991. So, this is prevention of liver cancer and then the human papilloma virus vaccine or HPV vaccine. This is given to young girls and boys nine to 11, or even a little bit older into teenage years if they’ve missed their earlier start for this. But human papilloma virus is sexually transmitted and causes approximately 99% of all cervical cancers. So, getting the HPV vaccine can actually reduce the risk by about 90% of getting HPV itself, which is what we know contributes to 99% of cervical cancer cases, but also contributes to vaginal, anal cancers, head and neck cancers, penal and vulvular cancers. So, HPV vaccine is certainly important for parents to look at for their young girls and boys.
Host: Okay. And how about Dr. Gluck going from talking there with LeAnn about vaccines, to talking about infections or any of those known to cause cancer.
Dr. Gluck: Right. There really is a wide spectrum of infections that are linked to cancer causation from viruses to bacteria, to parasites. The best known are the DNA viruses that can alter the tissue DNA. This is a process known as transformation. LeAnn has just mentioned an important example and that’s the human papilloma virus, particularly the strain HPV 16 and 18, hepatitis B to cause liver cancer, EBV Epstein-Barr virus is associated with Hodgkin’s and non-Hodgkin’s lymphoma and nasopharyngeal carcinoma.
So, those are the DNA viruses. The most widely known RNA cancer virus is hepatitis C, and it also can produce liver cancer. But bacteria also can be implicated. Infection with something called Helicobacter pylori, commonly abbreviated, simply as H. pYlori can cause cancer of the stomach and a form of lymphoma called a MALToma.
And finally and particularly important in other areas of the world, liver flukes which can come from ingesting uncooked fish, particularly in the more Eastern countries, can cause a form of bile duct cancer called cholangiocarcinoma. And finally, there’s an infection called schistosomiasis that’s linked to bladder cancer. So, it is a really a significant spectrum of infectious diseases that can trigger a cascade of events that lead to cancer.
Host: And Dr. Gluck, you mentioned earlier that so much progress in research and discovery has been made in recent years. In medicine, of course it’s often so much about what’s next. So, simply put what will cancer prevention look like in the near future?
Dr. Gluck: Right. So, I think as science marches on, we will better understand both our environmental risks and our food ingestion risks. We will understand better our ability to undergo genetic screening and counseling, to define risks, and then take a more focused approach to how to mitigate that risk of a subsequent cancer.
I think a huge part of where the future will go, already mentioned by LeAnn, will be vaccines. So, to actually prevent some of these viral infections in particular could have a massive impact on global health.
Host: Well, that certainly sounds like a major breakthrough. So, in wrapping things up here, for someone to learn more about their own personal cancer risk, why don’t you both tell us what’s available at Prisma Health. LeAnn, let’s start with you. What’s the first step?
LeAnn: At Prisma Health and the Center for Cancer Prevention and Wellness, we actually have a cancer prevention study. We call the study Prevent Cancer Greenville. This is open for anyone who is age 18 or older and speaks English. It’s a one-on-one visit. It is free to the participants. One-on-one with a nurse navigator and a research assistant who helps to educate that study participant on their own personal risk of cancer, by looking at the person’s past medical history, their family history, possibly the need to consider genetic testing, any infections or bacteria that they have been exposed to in the past and vaccines that they have had as well. So, all of this is looked at, in addition to their social history, environmental and occupational exposures, lifestyle habits, and behaviors.
So, basically they’re modifiable and non-modifiable risk factors, with all of that information in addition to a nutrition assessment and a physical activity assessment, the participant is educated on things that they can do to personally affect their risk of cancer. We also try to make sure that they are connected with a dietitian, with exercise resources. Also make sure that they are up to date on all the prevention screening recommendations by the American Cancer Society and get them connected where appropriate. So, that’s the population health part of that.
Host: And Dr. Gluck, did you want to add anything there? How does someone get connected with that study?
Dr. Gluck: Right. So, that is through our Center for Cancer Prevention and Wellness, and that can be done online or via telephone. I would add as LeAnn has talked about, the population approach when we try to look at this personally, this project personally defines many of what we are worried are risk factors based upon lifestyle or body composition. We know that the United States is in the top five of the worst countries in the world for cancer incidence. And when one says, why is that, that leads us to believe that a lot of it is lifestyle related. What we don’t do, what we eat, what we don’t eat and so on and so forth. So, this project is positioned to try to make an early link between lifestyle factors, such as exercise or lack thereof, body composition, be it lean versus, versus obese and try to link that to what I call or we call molecular signatures. So, we are collecting blood, buccal swabs, urine, and so forth. And in a year over year model of participation, we will develop a profile of patients’ lifestyle, dietary, exercise, and body composition parameters, and then seek to link them to molecular signatures, which has not yet been defined nor even for all practical purposes, explored.
Host: So in closing, it sounds as though all this great information you’ve given us really means that if people are wondering, how might this affect me? How much am I at risk? What can I do to find out? It certainly sounds as though there are some answers available to people through all the means you’ve mentioned. And for more information, you can go to PrismaHealth.org/Flourish. Dr. Larry Gluck and LeAnn Perkins of Prisma Health. Thanks so much again.
Dr. Gluck: Thank you.
LeAnn: Thank you.
Host: And if you found this podcast helpful, of course, we’d love for you to share it on your social media. And thank you again for listening to Flourish, a podcast brought to you by Prisma Health. I’m Joey Wahler.Read More
Find a doctor
Whether you’re looking for a primary care physician or need to see a specialist, we’re here to help with experienced, compassionate care near you.Find a Doctor