What Is Colorectal Cancer Screening?

A screening test is used to look for a disease when a person doesn’t have symptoms. (When a person has symptoms, diagnostic tests are used to find out the cause of the symptoms.) If you are age 50 to 75 years old, you should get screened for colorectal cancer.

Do the test to see if you are at risk for colon cancer.

Colorectal cancer almost always develops from precancerous polyps (abnormal growths) in the colon or rectum. Screening tests can find precancerous polyps, so that they can be removed before they turn into cancer. Screening tests can also find colorectal cancer early, when treatment works best. In most cases, colorectal screening includes a colonoscopy, a test iwhere a small instrument is placed into the rectum and colon and the inside of the rectum and colon are visualized. This procedure both finds and removes small clumps of cells on the inner lining of the colon. These are called polyps, and they can grow into cancer.

You are at an increased risk if you have one of the following:

  • a personal history of colorectal cancer or precancerous polyps
  • a family history of a first-degree relative (such as a parent or sibling) who had cancer or precancerous polyps in the colon or rectum before age 50, or multiple family members with colorectal cancer or polyps
  • a personal history of long-standing (more than eight years) inflammatory bowel disease, such as ulcerative colitis or Crohn’s colitis
  • a family history of familial adenomatous polyposis (FAP). This condition is a rare form of hereditary colon cancer. FAP can lead to the development of hundreds or thousands of polyps in the colon at a very early age. If left untreated, people with FAP will almost always develop colon cancer by age 40.
  • a family history of Lynch syndrome (formerly known as hereditary nonpolyposis colorectal cancer). This condition is caused by mutations in specific genes. It accounts for approximately 2 to 3 percent of all colorectal cancer diagnoses.

Colon cancer can be cured if found early enough. But the more that colon cancer grows, the more difficult it can be to treat.

  • For people with an average risk who have no symptoms, screening tests for colon cancer are recommended every ten years, starting at age 50.
  • People at a higher risk may benefit from earlier, more frequent screenings.
  • The U.S. Preventive Services Task Force recommends screening beginning at age 50. Some groups recommend starting earlier, at age 45.
  • The vast majority of new cases of colorectal cancer (about 90%) occur in people who are 50 or older.
  • Millions of people in the United States are not getting screened as recommended. They are missing the chance to prevent colorectal cancer or find it early, when treatment often leads to a cure.
  • If you think you may be at increased risk for colorectal cancer, learn your family health history and ask your doctor if you should begin screening before age 50.