Colorectal Cancer

Colon cancer (colorectal cancer) is cancer of the colon or rectum. It is currently the second leading cause of cancer death among men and women in Idaho, but it doesn’t have to be. Colon cancer can be prevented through regular screening.

Colon cancer almost always develops from precancerous polyps, which are abnormal growths in the colon or rectum. During a procedure called a colonoscopy, the polyps are removed before they turn into cancer. If everyone age 50 and over were screened for colon cancer, many colon cancer deaths would be prevented. Learn more key facts about colon cancer.

Screening Guidelines

It is recommended that beginning at age 50 (earlier if you have a family history), both men and women should use one of the screening tests below.

Tests that find polyps and cancer

• Flexible sigmoidoscopy every 5 years: A procedure to look inside the rectum and sigmoid (lower) colon for polyps (small pieces of bulging tissue), abnormal areas, or cancer. A sigmoidoscope is inserted through the rectum into the sigmoid colon. A sigmoidoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove polyps or tissue samples, which are checked under a microscope for signs of cancer.

• Colonoscopy every 10 years: A procedure to look inside the rectum and colon for polyps, abnormal areas, or cancer. A colonoscope is inserted through the rectum into the colon. A colonoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove polyps or tissue samples, which are checked under a microscope for signs of cancer.

• Double contrast barium enema every 5 years: A series of x-rays of the lower gastrointestinal tract. A liquid that contains barium (a silver-white metallic compound) is put into the rectum. The barium coats the lower gastrointestinal tract and x-rays are taken. This procedure is also called a lower GI series

• CT colonography (virtual coloscopy) every 5 years: A procedure that uses a series of x-rays called computed tomography to make a series of pictures of the colon. A computer puts the pictures together to create detailed images that may show polyps and anything else that seems unusual on the inside surface of the colon. This test is also called colonography or CT colonography.

Tests that mainly find cancer

With all of the following tests, you receive a test kit from your health care provider. At home, you use a stick or brush to obtain a small amount of stool. You may be asked to do this for several bowel movements in a row. You return the test to the doctor or a lab, where stool samples are checked for blood.

• Fecal occult blood test (FOBT) every year

• Fecal immunochemical test (FIT) every year

• Stool DNA test (sDNA), interval uncertain

Talk to your doctor to find out which screening test is right for you.
For more detailed information about colon cancer, check out the interactive online tutorial from the National Library of Medicine. It explains the anatomy, causes, symptoms, diagnosis, and treatment options for colon cancer.

Take the Colon Cancer Risk Assessment to better understand the potential risk factors involved in developing colon cancer.