Colorectal Cancer Screening Guidelines
March is Colorectal Cancer Awareness Month. Colorectal Cancer is one of the leading causes of cancer deaths in the United States, but advances in early detection and treatment make it one of the most preventable and treatable forms of cancer. In this first episode of the 2020 Colorectal Cancer Awareness Month series, Gautam Mankaney, MD joins Butts & Guts to discuss recommended screening guidelines and methods.
Colorectal Cancer Screening Guidelines
Scott Steele: Butts & Guts, a Cleveland Clinic podcast exploring your digestive and surgical health from end to end.
Hi everyone, and welcome to another episode of Butts & Guts. I'm your host, Scott Steele, the Chair of Colorectal Surgery here at the Cleveland Clinic in beautiful Cleveland, Ohio. We're very pleased today to have Dr. Gautam Mankaney, who is a staff physician in the Department of Gastroenterology, Hepatology, and Nutrition here at the Cleveland Clinic. Welcome to Butts & Guts.
Gautam Mankaney: Thank you for having me.
Scott Steele: I always like to start out with all of our guests and just give a little bit of background. Where are you from? Where'd you train? How did it come to the point that you're here at the Cleveland Clinic?
Gautam Mankaney: Great. I was born in Hong Kong. I moved to the West Coast when I was 10. Then started my medical training in the Midwest at the Ohio State. I've been in love with the Midwest ever since. Completed fellowship at the Cleveland Clinic. I was really inspired by my interactions with patients and the staff, so I decided to stay.
Scott Steele: Oh, fantastic. Again, we're so glad that you're here. We're going to talk today about colorectal cancer screening guidelines. March is Colorectal Cancer Awareness Month. We know that colorectal cancer in and of itself is, depending on the year, the second or third leading cause of cancer-related death in the United States. A part of this, I always tell my patients, is that colorectal cancer is one of the ones that we can detect early or even get in the pre-cancerous stage. We're going to really focus upon that today. Before we get into the details about screening, can you give our listeners a little bit of an overview? We've had this on past [episodes], but what is colorectal cancer, and how does somebody develop into this cancer, and what are some of the risk factors for that?
Gautam Mankaney: Cancer, essentially, is when cells start dividing abnormally, escape their growth cycle, and then turn into little growths. When that happens in your colon or rectum, it's called colorectal cancer. Generally, it starts off with the little piece of tissue that grows over time. That's a 10 to 20 year process, and eventually you get your cancer. Now risk factors for colon cancer include, so think of all the unhealthy things, so eating a lot of red meat, eating a lot of processed meat, lack of physical activity, or not eating that many vegetables. Some people have other risk factors which they're born with, so genetic factors. They have a lot of colorectal cancer in their family, or they have a syndrome in which people get colorectal cancer. There's many components that increase your risk of having it.
Scott Steele: One of the things that we talk about in terms of treatment of colorectal cancer is the colon and the rectum. We tend to bring those together. Just in general, an overview, how is colorectal cancer treated?
Gautam Mankaney: When you find the cancer early, that's when it's either a pre-cancer or a very early stage cancer. It hasn't moved anywhere else in the body, or it hasn't grown past the area of the colon or the rectum, many times we can endoscopically treat it. That's through a procedure where we just cut it right out. Once it grows past that, then we have to the expertise of other physicians on our team. Depending on the stage and how widespread it is, it may mean chemotherapy, radiotherapy, or surgery, and depending on where you are in the organ too. The colon is a meter to a meter and a half long. The very end of it is called the rectum. That's where stool collects before you poop it out. Depending on where you are in the colon determines what type of treatment you get.
Scott Steele: We're going to focus in now on colorectal cancer screening methods. We'll just talk about the different tests themselves. Some of these are used more often, and some of these are used less often, and are maybe even a little bit more historical or very specific insistence purposes. Let's first start out with either a barium enema or an air contrast barium enema. What is that?
Gautam Mankaney: There are many types of tests to look for colon cancer. Some of these tests are stool-based tests and some allow direct visualization. Direct visualization means it's exactly what it sounds like. In that category you have a imaging tests. That's where your barium enema falls in. Essentially what the radiologists do is they instill barium into your colon. Barium is something that you can visualize with some sort of x-ray machine. What they're looking for is those little bumps, the growths I talked about, on the inside lining of your colon. When they see it, they assume it's either a cancer or a big polyp.
Scott Steele: You also talked about direct imaging tests. There's something that's called a flexible sigmoidoscopy and a colonoscopy. What are the differences between the two? Why would you use one versus the other?
Gautam Mankaney: A colonoscopy and a flexible sigmoidoscopy. What essentially it is, is a thin long tube with a camera on the end and it allows you to see inside the organ. A colonoscopy allows you to see the whole colon, so it's longer than a meter and it helps you get to the very end of the colon. Prior to a colonoscopy you have to do a bowel prep to improve your visualization.
A flex sig, the way I like to think about it is it's a half colonoscopy so it only sees the distal end, the end of the colon, and mostly the rectum. The good news about a flex sig is you don't need a bowel prep. One of the cons about it is you don't get to see the whole colon. We know you get colon cancers on the left side and the right side, the right side being the far end.
Scott Steele: Why would you get a flex sig in and of itself?
Gautam Mankaney: A couple of reasons to get a flex sig. One is if you don't want a colonoscopy, let's say, or if you have symptoms which make us think maybe there's something going on in the rectum. Perhaps if you're on the younger side. In younger people we tend to see colon cancers on the left side of the colon, so that's the far end. Those are other reasons to do a flex sig.
Scott Steele: One of the other things you mentioned is this category talking about stuff in the stool, whether it be a fecal occult blood test, a stool sample that you could send home with, or even the newer ones, the stool DNA. What are those all about? If they're positive, what happens next?
Gautam Mankaney: When that little growth turns into a cancer... Like I said earlier, it takes about 20 years. In that process it may start bleeding. Sometimes you don't see that blood. It may be just a drop or two of blood. What these other stool-based tests do is they try and find that blood that the little cancers, or the polyps, lose into your colon. Again, you may not be able to see it. The plus side is you don't need a colonoscopy if it's negative. But if you find something with these stool-based tests, you still don't know what's causing the bleeding. You still don't know where it is. You still will need a colonoscopy if positive.
Scott Steele: How are these stool DNA tests? How are they done? What are they testing for?
Gautam Mankaney: Blood has a two components to it. It's a protein, and it also has a ring that holds iron in it. Depending on the type of stool-based test you use, it's looking at the different components of that protein. You may have heard of fecal immunochemical testing, or fit testing. That's one type, or a fecal occult blood testing. As you had asked earlier, we have these newer tests that look at DNA. When these cells that turn into polyps, or turn into cancer, something's wrong with them. They're not your typical body cells. They have weird or abnormal DNA. They shed that into your stool. These new tests are also looking for that DNA.
Scott Steele: Yeah. I think it's important again to just highlight the fact that you do oftentimes need to have a follow-up test to see what's going on. That often involves a colonoscopy. Truth or myth? A colonoscopy is the best screening and prevention tool for colorectal cancer?
Gautam Mankaney: I'm a little biased on this one because I am a gastroenterologist, but I think that's the truth. The reason I think it's the truth is it allows you not only to find the cancer, or find the pre-cancers, but you get to take them out at the same time.
Scott Steele: Before we go on here, you mentioned something earlier about having a colonoscopy. The worst part, or I guess the part that a lot of people fear more than anything, is the prep. Can you kind of explain the process of the prep? Why do you do it? What's to be expected? Take some of the mystery out of this bowel prep.
Gautam Mankaney: Yeah. Absolutely. Polyps are tiny. Polyps, again, are those pre-cancers. Cancers can be very tiny. They come into all sorts of shapes and sizes. They can be completely flat and they sit on the inside lining of your colon. They range in size from a millimeter to one or two centimeters. If you have a little stool left in there covering that polyp, you may not be able to see it. The purpose of the prep is to clean out all that stool to give a you the best possible chance of finding all those lesions. Previously, preps used to be large quantity. You had to drink four liters of fluid and that's hard for anyone to do. It only came in one flavor. Now we've come up with all these types of preps that come in different quantities, different tastes, and different ways of taking it to make the process easier for you.
Scott Steele: Yeah. As someone who tries to practice what they preach, I can tell you that the prep is not as bad as I thought it was. It's certainly something in the easy test to be able to do so that we can get a colonoscopy. The last thing that gets asked is, can't you just get the CT scan, a CT colonography? How does that role in terms of screening or surveillance? Do you have to take a prep with that?
Gautam Mankaney: I think you hit on a really good point with that question. The two types of tests, direct visualization and stool-based tests. Under direct visualization, you have CT tests. That's basically a CAT scan of your colon. They're looking kind of like that barium enema. They're looking for growths inside your colon. Pros to it are it's a cat scan. It's quick. But some cons that people don't think about is you still need to prep. You still need to get the stool out of your colon in order to see those polyps and pre-cancers. You have to do it more frequently than colonoscopy. Then you're getting a little small dose of radiation as well.
Scott Steele: We're here to focus on screening guidelines. I think the first question, very briefly, is what's the difference between screening and surveillance?
Gautam Mankaney: Good question. If you are an average risk person, that means you're an individual who doesn't have a predisposition towards developing colon cancer, and you're coming for your first test, we call it screening. That usually starts somewhere between the ages of 45 and 50. If we find a polyp, or we find a cancer, or you have some sort of risk factor, let's say you have a genetic condition that predisposes you towards colon cancer, then we call it surveillance because you're at higher risk to have something in there.
Scott Steele: Yeah. I know we're going to get into this a little bit, but it also affects how often we need to get these screening or surveillance methods. You did talk a little bit earlier, touched on this, but specifically now as it relates to when you should get a screening or surveillance examination, how do these risk factors of family history, or even race, play into the timing of when you should get your first examination?
Gautam Mankaney: Yeah. Traditionally, we used to say your first examination starts at 50 years old. It went from 50 to 75. What we know is, as far as race goes, that African-Americans have higher rates of colon cancer. When they get colon cancer, it's at a later stage. What our society guidelines, that's several experts who study this subject, recommended that, if you're African-American, you start at 45.
Now we've been screening for almost two decades, and we're finding that colon cancer rates are decreasing, except young people are getting more cancer. Because of young people getting more cancer, The American Cancer Society has recommended that everyone should start at 45. Right now, the start age that I tell people is, if you're African-American, 45. Then, for everyone else at average risk, somewhere between 45 and 50.
Scott Steele: Yeah. Also, how does family history play into this apart from the genetic syndromes that you mentioned earlier? If my first-degree relative, my mom or my dad, had colorectal cancer at age 50, would that affect the timing of when I get my first examination?
Gautam Mankaney: Absolutely. In your family, if your dad had colon cancer at 50 let's say, then you would start 10 years before that, so you would start at 40. If there's any colon cancer in a first-degree of relatives, so that's your mom, your dad, your brother, your sister, or your kids, you start 10 years younger than when they had their colon cancer or at the age 40, whichever came first. If you have multiple first-degree relatives, then you start at 40 as well.
Scott Steele: You mentioned briefly about this kind of ongoing thing that's even hit the lay media that talks a little bit about the rise in colorectal cancer in young people, in that it's essentially doubled as young as their 20s since the 1980s. Why do you think we're seeing a higher number of younger colorectal cancer patients?
Gautam Mankaney: It is an alarming rise because it's in such young people. When we see cancers in them, we're finding a lot more of these genetic syndromes that I was talking about. That's one possibility. The other big reason is, I think, we're changing as people. We're becoming more unhealthy, as I touched upon in the beginning. Our younger generation, less physical activity, more obesity, more processed foods, more red meat. We think this is all playing into their higher cancer rates.
Scott Steele: We talked a little bit about the fact of when you get your first examination. I know there's a lot of nuances in individuality. It's hard to make sweeping recommendations but, in general, if a person gets a colonoscopy, when should they get their next colonoscopy? How does the findings of that first colonoscopy affect when you'd get that follow-up?
Gautam Mankaney: If you have a normal colonoscopy, you can assume that you're going to have one per decade, one every 10 years.
Scott Steele: Assuming you're of average risk?
Gautam Mankaney: Assuming you're at average risk. If you have something in your colonoscopy, whether it's a polyp or a cancer, we look at all sorts of factors. We'll look at the size of the polyp, the number of the polyps, and the type of polyp it is. We send it to a pathologist, a doctor that will look at it under a microscope and tell us what type of polyp it is. Based on that, we'll determine how often your interval is. Those intervals usually vary between three to five years for the most part. On a rare case, if it's very high risk, we'll do it every year.
Scott Steele: Yeah. I think that's a good point. Even sometimes you might find something that we think is a polyp. It turns out to be essentially just a benign growth that has nothing to do with polyps and that interval may extend out to 10 years. It's important that you discuss with your doctor when you should get that next follow-up scope. We talked a little bit about screening surveillance, but there's something else that's called a diagnostic colonoscopy, somebody who's got symptoms. What are some of the symptoms of colorectal cancer that may spurn somebody to get a scope of some sort, or an evaluation of some sort, that may be even a little bit outside of the guidelines that we're talking about today?
Gautam Mankaney: When colon cancer presents with some sort of symptom, it could be bleeding. If you see a little blood in your stool, that's something that makes us think about cancer. Some people, their stool starts changing shapes. If you think about it, there's something in your colon, and that's going to change the shape of your stool. If it becomes more narrow, if you have a change in your stool habits, let's say you now have a lot of diarrhea or a lot of constipation that goes for more than a week or so, that's a symptom. If you've been losing blood and you don't know it, a lot of us can't see the bleeding, your blood counts drop. When your blood counts drop, you get more winded, you get short of breath, you feel lightheaded.
Gautam Mankaney: Then if you're losing weight and we can't explain why. If it's not because you're dieting, you're just losing weight, that's also a reason. Interestingly, abdominal pain is rather rare. Something I want to emphasize here is the reason screening is so important and so effective is because colon cancer usually doesn't present with symptoms until it's at a later stage. We have 10 or 20 years to find it when you don't have symptoms.
Scott Steele: Final take home message for our listeners as it pertains to screening guidelines, what is the take home message that you want our listeners to reveal and say, I need to do this?
Gautam Mankaney: Yeah. Out of all the cancers that we have, colon cancer is one of the most preventable. It's fortunate we have so many different tests that we can use to look for colon cancer. If you find a colonoscopy daunting, don't worry. Ask your physician and we can talk about all the various methods you have to find colon cancer.
Scott Steele: Well, that's wonderful stuff and I couldn't agree more as a colorectal surgeon. We always like to wind up with our guests to know a little bit of more about you with some quick hitters. What is your favorite sport?
Gautam Mankaney: Tennis.
Scott Steele: What is your favorite food?
Gautam Mankaney: Cheese, anything with cheese.
Scott Steele: What is the last nonmedical book that you've read?
Gautam Mankaney: Theory of Everything by Stephen Hawking
Scott Steele: Finally, tell us something that you like here about beautiful Cleveland, Ohio.
Gautam Mankaney: I love the public park system. In the winter that's cross country skiing, and in the summer it's a lot of running.
Scott Steele: I could not agree more. To learn more about colorectal cancer prevention and treatment, please visit clevelandclinic.org/coloncancer. That's clevelandclinic.org/coloncancer. For additional information, or to schedule a colonoscopy, please call (216) 444-7000. That's (216) 444-7000. Gautam, thanks so much for joining us on Butts & Guts.
Gautam Mankaney: Thank you for having me.
Scott Steele: That wraps things up here at Cleveland Clinic. Until next time, thanks for listening to Butts & Guts.