I recently turned 50 and my doctor recommended I get screened for colon cancer. Is that really necessary? What does a screening involve?

Colon cancer is the #2 cause of death from cancer in the U.S. Contrary to what many people believe, it is not a "man's disease." Colon cancer strikes men and women equally. Nine out of 10 cases of colorectal cancer (cancer of the colon or rectum) occur after age 50.

The good news is that colorectal cancer can be prevented. Colorectal cancer starts as small growths, called "polyps," that form inside the colon or rectum. In time, some of these polyps can turn into cancer. If you find the polyps early and remove them before that happens, you won't get colorectal cancer. That's why screening is so important. It can find polyps before they become cancerous. Screening can also detect cancer in its earliest stages, when it's most likely to be cured.

There are several methods of screening for colorectal cancer:

Fecal occult blood test (stool test) checks for blood in your stool. At home, you put a small sample of your stool on a special test card. You do this for three bowel movements in a row, then return the test cards to your doctor or a lab. This test should be done once a year.

Flexible sigmoidoscopy involves the doctor putting a short, thin, flexible, lighted tube into the rectum. The doctor can look for polyps in your rectum and the lower third of your colon. This test is usually done every 5 years.

Double contrast barium enema is an x-ray of your colon. First, you are given an enema with a liquid called barium, which makes it easy for the doctor to see the outline of your colon on the x-ray. This test is done every 5-10 years.

Colonoscopy is considered the "Gold Standard" for cancer screening. It is similar to sigmoidoscopy except that the doctor uses a longer tube that can check for polyps or cancer inside the entire colon. The doctor can also remove polyps during the colonoscopy. And because you are sedated, most people feel little or no discomfort. This test is done every 10 years.

Virtual colonoscopy is a new, less-invasive procedure available at Methodist. It involves the same prep as a traditional colonoscopy, but you are not sedated for the procedure. A small burst of air is used to expand the rectum and colon, and an ultra-fast CT scanner with special "virtual reality" software looks for polyps. If a polyp is found, you will need to have it removed using conventional colonoscopy.

Currently, virtual colonoscopy is not covered by most insurance companies. But most insurance plans and Medicare help pay for other screening tests, including traditional colonoscopy, for colon cancer in people age 50 or above.

The American Cancer Society recommends that colorectal cancer screening begin at age 50. Talk to your doctor to decide which screening test is right for you.

Dr. Lindstrom is a physician with Methodist Medical Group at Metamora. She is board-certified in family practice, providing outstanding medical care for patients of all ages.