Colon Cancer Screening and Prevention

There are various screening tests that may detect pre-cancerous or early cancerous changes in the colon in hopes of diagnosing the cancer at an early, more treatable stage.

Although not all colon cancers can be prevented, you can reduce your risk by limiting the alcohol you drink, exercising and maintaining a healthy diet and weight. Some patients may also be advised to take vitamin D, though this will not be recommended to certain patients with other health conditions.

Beginning at age 45, men and women should be screened for colon cancer. Take part in one or more of the following colon cancer screenings. A colonoscopy is an outpatient procedure that examines the colon and rectum for polyps, cancer, ulcerations, diverticulitis and other abnormalities. A long, thin, tube-like instrument (called an endoscope/colonoscope), with a light and a lens for viewing, is gently inserted through the rectum and moved through the colon. This procedure, or a similar one, should be done at least every 10 years.

While a colonoscopy is the primary screening method, your care team may recommend other screening tests, including the following:

  • Virtual colonoscopy is a computer-assisted approach that is less invasive than traditional colonoscopy. This procedure, or a similar one, should be done every five years.
  • Fecal occult blood test (FOBT) or fecal immunochemical test (FIT) checks stool for blood that can only be seen with a microscope. This procedure should be done every year.
  • DNA tests check the stool for small pieces of abnormal DNA that may be cancerous in cells lining the colon and rectum.
  • Sigmoidoscopy is a diagnostic test to check the lower part of your colon or large intestine (the sigmoid colon). This procedure, or a similar one, should be done every five years. Watch this video to learn more.
  • Double-contrast barium enema is an imaging test that uses X-rays to look at your lower gastrointestinal (GI) tract, including your colon; should be done every five years.
  • Special blood tests

People with colon cancer risk factors should begin screening procedures at an earlier age and/or be screened more often.

Our team may recommend some patients diagnosed with colon cancer and their close family members to undergo genetic testing, particularly young patients and patients with a family history of two or more primary relatives with colon or rectal cancer, especially if these cancers occur at a young age. Genetic testing looks for potential inherited genetic variants that could have contributed to developing colon cancer. Genetic counselors work with patients on a detailed family history analysis and genetic evaluation. Using state-of-the-art molecular tests, genetic counselors will arrange for testing of a sample of blood or saliva for certain changes in genes that may increase a person’s risk of developing colon cancer and possibly other cancers.

Learn more about colon cancer screening and the Center for Community Health and Health Equity’s (CCHHE) colorectal screening program.

Read this article about the ability of vitamin D to protect some people from developing colorectal cancer.

Learn more about Brigham and Women's Hospital


For over a century, a leader in patient care, medical education and research, with expertise in virtually every specialty of medicine and surgery.

About BWH