Not often talked about, colon cancer — cancer of the colon or rectum — is the second leading cause of cancer-related deaths in the United States for both men and women combined.

• What is Colon (Colorectal) Cancer?
• Risk Factors
• Symptoms
• Common Screenings and Tests
• Treatment Options
• Further Reading on Colon Cancer

What is Colon (Colorectal) Cancer?

Colon, or colorectal, cancer is the abnormal growth of cells in either the colon or the rectum. According to the American Cancer Society, colon cancer is the third most common cancer in both men and women.
Colon/colorectal cancer overview
Diagram of large intestine
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Risk Factors

While the cause of colon cancer is not known, it appears that many colon cancers are preventable. Physical inactivity, having a diet that is high in fat and includes a lot of red meat, obesity, smoking, and alcohol use all increase your risk.

• Diet and Exercise - Getting regular exercise, eating a diet of fruits, vegetables and whole grains and limiting fats may help prevent getting the disease.
• Aging - The risk for developing colon cancer increases as you age. Over 90 percent of colorectal cancers are diagnosed in people over age 50¹. Both men and women are at risk for colon cancer.
• Family History - Having family members who have diagnosed with colon cancer, colon polyps, or other cancers increases your risk. Discuss this with your doctor.

Read more:
What increases your risk?
Preventing colon cancer
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Symptoms

Warning signs of colon cancer include:

• Rectal bleeding
• Blood in the stool or a change in bowel habits
• Unexplained weight loss
• Constant fatigue
• Nausea or vomiting

Read more about warning signs and symptoms
These may also be warning signs of less serious illnesses, so please discuss these symptoms with your doctor.
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Common Screenings and Tests

Colon cancer may be prevented by undergoing regular screening tests.

American Cancer Society Guidelines on Screening and Surveillance for the Early Detection of Colorectal Adenomas and Cancer - Average-Risk Women and Men Ages 50 and Older

The following options are acceptable choices for colon cancer screening in average-risk adults. Since each of the following tests has inherent characteristics related to accuracy, prevention potential, costs and risks, individuals should have an opportunity to make an informed decision when choosing a screening test.

Test		Interval (beginning at age 50)		Comment
Fecal Occult Blood Test (FOBT) & Flexible Sigmoidoscopy		FOBT annually and flexible sigmoidoscopy every 5 years		Flexible sigmoidoscopy together with FOBT is preferred compared with FOBT or flexible sigmoidoscopy alone. All positive tests should be followed up with colonoscopy.*
Flexible Sigmoidoscopy		Every 5 years		All positive tests should be followed up with colonoscopy.*
Fecal Occult Blood Test		Annually		The recommended take-home multiple sample method should be used. All postive tests should be followed up with colonoscopy*+
Colonoscopy		Every 10 years		Colonoscopy provides an opportunity to visualize, sample and/or remove significant lesions.
Double Contrast Barium Enema		Every 5 years		All positive tests should be followed up with colonoscopy.

+
If colonoscopy is unavailable, not feasible, or not desired by the patient, double contrast barium enema alone, or the combination of flexible sigmoidoscopy and double contrast barium enema are acceptable alternatives. Adding flexible sigmoidoscopy to DCBE may provide a more comprehensive diagnostic evaluation than DCBE alone in finding significant lesions. A supplementary DCBE may be needed if a colonoscopic exam fails to reach the cecum, and a supplementary colonoscopy may be needed is a DCBE identifies a possible lesion, or does not adequately visualize the entire colorectum.
+There is no justification for repeating FOBT in response to an initial positive finding.

Note: Screening guidelines may be different for individuals at increased risk or high risk.

Detailed Descriptions of Exams and Tests
Exams and tests
Fecal occult blood test (FOBT)
Flexible Sigmoidoscopy
Double-contrast barium enema
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Treatment Options

Treatment overview
Surgery
Radiation therapy
Chemotherapy
Medications
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Further Reading on Colon Cancer

• Should I have a sigmoidoscopy or a colonoscopy to screen for colorectal cancer?
• What are clinical trials?
• What side effects or complications might I have from treatments?
• How often will I see my health care professional?
• What happens if my colon cancer comes back?
• How can I prepare for end-of-life issues?

Other Information from the National Cancer Institute

• Colorectal Cancer: Prevention - Patient Information
• Colorectal cancer: Screening - Patient Information

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