ANNOUNCER: Cancer of the colon and rectum is called colorectal cancer, and it's the fourth most common cancer in the United States.
Doctors recommend that everyone over age 50 should be regularly screened for colorectal cancer, but some people should be screened earlier.
RICHARD GOLDBERG, MD: If you have a family history of colon cancer you should be screened 10 years before the youngest affected relative. So if a relative of yours - a sister or a parent - had colon cancer at the age of 40, you ought to be screened at 30.
ANNOUNCER: There are several tests that are used to screen for cancers of the colon.
EDWARD CHU, MD: The traditional test that the American Cancer Society and the Centers for Disease Control have strongly recommended is fecal occult blood testing. So to simplify that, that is actually testing one's stools for the presence of blood, as well digital rectal exam.
ANNOUNCER: A sigmoidoscopy is a test performed by a gastroenterologist. A tube with a tiny TV camera and light is inserted into the rectum and distal portion of the colon, to screen for abnormalities.
RICHARD GOLDBERG, MD: The trouble is the sigmoidoscopy only looks at the bottom foot and a half of the colon and the colon is about 6 feet long.
ANNOUNCER: In order to examine the entire colon, gastroenterologists prefer to perform colonoscopies.
EDWARD CHU, MD: So what colonoscopy is, is a - basically a tube that's inserted through the rectum and goes all the way up through the large intestine. So it can visualize the entire colon.
ANNOUNCER: Sometimes abnormal growths called polyps are found in the colon during these exams.
RICHARD GOLDBERG, MD: Many times, early stage colorectal cancers will develop on a polyp. And sometimes these polyps are actually on a stock so that they sort of look like a mushroom with the top of the polyp being the polyp and then the stem of the mushroom being the stock.
What a colonoscopist can do is actually put a snare around the bottom of the mushroom and use a little electric current to pull that off and retrieve it.
ANNOUNCER: The biopsied tissue is sent to a lab where a pathologist will test it for cancer. If the sample tests positive, an oncologist will run more diagnostic tests to determine how far the cancer has spread.
EDWARD CHU, MD: So stage I, the tumor is really just confined to a very limited part of the colon. Stage II it, it involves the entire thickness wall of the colon, if you will. Stage III not only involves the entire thickness of the colon but also now has extended to the local regional lymph nodes. And then stage IV is beyond that.
ANNOUNCER: Most doctors treat early stage cancer with surgery alone.
RICHARD GOLDBERG, MD: Well, the nice thing about how you treat early stage colorectal cancer is that all you have to do is take it out. Now there are two ways these days that we're doing colon surgery. One is laparoscopic colectomy where a patient will get four little stab wounds and then about a 4-inch incision to remove the colon, in order to remove a section of the colon. The older operation that's more commonly done is called a standard colectomy and that ends up with about an 8-inch incision in the abdomen.
ANNOUNCER: Most times surgery will cure early colorectal cancer. But there is ongoing debate whether to treat stage II patients with chemotherapy after surgery.
EDWARD CHU, MD: There is tremendous data both from the United States and from Europe that once surgery is performed, patients if they're in good performance status, good shape, they should receive what's called adjuvant chemotherapy. So that means giving cancer drugs for a period usually of 6 to 8 months. And the rationale for giving the chemotherapy after surgery has been performed is to try and prevent the cancer from coming back at the local site, but also trying to prevent the cancer from spreading to other distant sites.
ANNOUNCER: Surviving colorectal cancer can ultimately depend on how early it is diagnosed.
RICHARD GOLDBERG, MD: The 5-year survival rate for somebody with a stage I cancer, a cancer just affecting the inner layer of the colon, is 95 percent. The likelihood that somebody with a stage II cancer that's affecting the muscle layer of the colon but not the lymph nodes is about 80 percent. This again underscores the reasons for trying to detect colon cancer early. It can make a big difference in terms of odds of cure.