Transcripts: 513-1 and 513-2

Week: 513.1 Guest: Robert Mathieson, M.D. Topic: Colon Cancer - Part One Host: Richard Roeder Producer: Ed Graham

NEMA: This is the first half of a discussion on colon cancer with Dr. Robert Mathieson, Chief of Gastroenterology at the Union Memorial Hospital in Baltimore, Maryland.

NEMA: Dr. Mathieson, is colon cancer remaining at a seemingly fixed rate in the United States of occurrence or is it on the decrease or is it on the increase?

MATHIESON: Colon cancer still remains one of our most prevalent cancers. It's the most common cancer behind lung and breast cancer and there are approximately 140,000 new cases of colon cancer a year in the United States so it is not necessarily increasing but it certainly is not decreasing.

NEMA: Who is the most likely victim of colon cancer? Is this again something that's far more likely as you get older or can colon cancer occur in the very young?

MATHIESON: Colon cancer seems to increase in incidence after the age of 50 and it affects both sexes although maybe men slightly more than women but is still quite prevalent in both sexes. It is cancer that occurs as we get older which is why we recommend that all patients over the age of 50 should start going through screening procedures to check for colon cancer.

NEMA: Talk a little bit about what those screening procedures are.

MATHIESON: This is again a sort of a controversial area because to try to do anything about a cancer, you're going to want to detect it early. You want to be able to find it early before it's had a chance to grow or spread and that's where you can do something about decreasing the incidence of a particular cancer. Unfortunately we don't have any great tests right now that help us do that with colon cancer. We have several things that we do pretty much in concert that together may help increase our ability to detect early cancers and in fact there are studies now that clearly show that but basically the things that we do are to check their stools for blood by doing these little hemocult cards and we have to do a screening test, usually with a flexible scope to look into the colon maybe in concert with a barium enema or colonoscopy to try to look for signs of cancer or polyps, polyps being the earliest form of a colon cancer growth that are usually benign at this point but we do firmly believe that cancer arises from polyps so if you have a colon polyp, you need to remove it so you can prevent cancer from occurring later in life.

NEMA: Does there seem to be a hereditary link between colon cancer, again whether grandparents, parents or sisters, brothers?

MATHIESON: There is a very strong genetic link that has been seen and you may have heard that - and particularly at Johns Hopkins - they have identified genetic links.

NEMA: Join me for the second half of my discussion on colon cancer with Dr. Robert Mathieson.

Transcripts:

Week: 513.2 Guest: Robert Mathieson, M.D. Topic: Colon Cancer - Part Two Host: Richard Roeder Producer: Ed Graham

NEMA: This is the second half of a discussion on colon cancer with Dr. Robert Mathieson, Chief of Gastroenterology at the Union Memorial Hospital in Baltimore, Maryland. I asked Dr. Mathieson about heredity and colon cancer.

MATHIESON: The genetic link seems to only affect about 10% - 15% of all colon cancers so don't have everyone run down and get their chromosome mapping done because it's not going to be helpful for the general population for detecting colon cancer. It would be helpful in those families where it is known that there is an increased risk of colon cancer to predict whether someone might get it or not but that only affects, like I said, about 10% or 15% of all colon cancers found.

NEMA: Okay. In the more average case where there's not this obvious hereditary link with colon cancer, how much of a role and I know this is something that gets bounced around a lot in the medical and research community, how much of a role does diet play in your belief in the development of colon cancer?

MATHIESON: Well, I think that we don't really have a clear idea about diet and its actual role in colon cancer. We do have some epidemiological evidence that seems to suggest that if you - in Africa and certain undeveloped areas of the world since they tend to eat a lot coarse fiber, whole grain foods and very little in the way of fat, colon cancer is of a low incidence in these countries. So again we feel that in our American diet where we eat too many fast foods and too much fat in our diet, that high fat diets, low fiber diets tend to enhance or increase the risk of colon cancer and again there's no absolute proof to that in terms of any studies but this is sort of epidemiological studies where they've looked at the incidence of colon cancer in various countries.

NEMA: How is colon cancer treated and I realize that this is a complicated question to give a simple answer to because as you pointed out, the earlier you detect something, the better chance you have of dealing with it but first, how is it treated and secondly, how successfully is it treated in terms of extending a person's life to a normal life span?

MATHIESON: The successful treatment of colon cancer, of course, depends on identifying the cancer very early or as early as you possibly can. If the cancer is found in a polyp then the polyp can be removed, and that almost insures total recovery from the cancer and a complete cure. If the cancer involves more of the bowel, the actual wall of the bowel, then it really depends on whether the cancer has spread into the tissues. Fortunately most cancers that we find are usually confined to the lining of the mucosa and not deeper than that and if that is the case then people have an excellent prognosis. The five year survival rate in that situation may be as high as 75%-80%.