Health Library

Colorectal cancer is the fourth most common cancer in the United States. In colorectal cancer, cancer cells grow in the colon, rectum or both. When detected early, it's one of the most treatable forms of cancer.

Factors that place you at a higher risk for colorectal cancer are:

• Age. According to the American Cancer Society, more than 80 percent of people diagnosed with colorectal cancer are over age 50.
• Adenomas (polyps). These growths of the colon and rectum can be pre-cancerous and can signal that you are at increased risk for colorectal cancer. Most adenomas will not turn into cancer. However, regular screening to remove them reduces your risk of developing colorectal cancer.
• Diet. A diet high in red meat may increase your risk of colorectal cancer.
• Family history.
  • Having a first-degree relative — a parent, sibling, or child — with colorectal cancer may double your lifetime risk of developing colorectal cancer.
  • If a first-degree relative has had colon polyps, you are at a higher risk.
  • If you have a family history of hereditary colorectal cancer syndromes, such as Lynch syndrome or familial adenomatous polyposis (FAP), you may get referred to our Center for Cancer Genetics and Prevention to be screened.
• Inflammatory bowel disease (IBD). Autoimmune conditions, such as Crohn's disease or ulcerative colitis, increase your chances of developing colorectal cancer.
• Prior diagnosis. If you've had colorectal cancer, you are at increased risk for developing a second cancer later in life.

Screening recommendations

Screening for colorectal cancer is highly effective and can reduce your risk of both developing and dying from the disease.

Ages 18-39: Screening is usually not necessary unless you have IBD, a concerning history of many cancers in your family, or hereditary syndromes such as Lynch syndrome or FAP. If this is the case, your provider may recommend screening at a younger age, usually 10 years earlier than the time the youngest person in your family was diagnosed.

Ages 40-45: Review your risks annually with your provider. You may need to begin screening if you're at increased risk or if you've had adenomas.

Ages 45+: Everyone should be screened. Acceptable forms of screening can include a colonoscopy, sigmoidoscopy and/or annual stool occult blood. Based on your risk profile, your health care provider can help you decide which test is appropriate for you.

People with a family history of colorectal cancer and/or other cancers in several close relatives across generations, especially if these cancers occur at a young age, may benefit from genetic counseling and testing. Learn more through our Center for Cancer Genetics and Prevention.

Related links

Find out whether you should get a colonoscopy.

Read a study that reinforces the value of colonoscopy screening for prevention.