Nancy Kemeny, MD: It can be hereditary. There are two different types that are definitely hereditary.One is called familial adenomatous polyposis where the patient has multiple polyps in the colon and they carry that trait down to their children, and when that happens,it is, you have a very high risk of colon cancer, so you should know if one of your family members has that and you have to be screened very early.Then there's another form called nonpolyposis colon cancer, or HNPCC is another term they use for it.And in this, again you should know if your family has this, and the way you can find out about this is if you know for instance that your father,your grandfather had colon cancer, on the same side, let's say on the father's side, and they also, and the sister maybe on that side had uterine cancers, some increased family history like this.
Nancy Kemeny, MD (cont.): You should really discuss that with your physician, because there are these families that have a higher incidence of cancer, and one of them being colon cancer.And those families have to be screened much more than the regular population. So if you know you're one of those families,sometimes they start screening even at 20 years old, you know at a much earlier time. Even if you're not one of these genetic families,like if you have just a father, or just a mother with colon cancer, you should be screened 10 years before their cancer.So for instance, if they were 50 years old when they developed, you should start screening at 40.So there could be a slight increase just because you have one family member, even if you don't have one of these families that cancer.