Medscape March 10, 2009
Author: Zosia ChusteckaCME Author: Charles Vega, MD, FAAFP
Colonoscopy every 10 years, starting at age 50 years, is the preferred strategy for colorectal cancer screening, say new guidelines from the American College of Gastroenterology (ACG).
The ACG recommends presentation of a "preferred" strategy to a "menu of options" in discussing screening for colorectal cancer with patients. The latter approach is more complex and may result in reduced adherence to screening among patients and clinicians.
- Colonoscopy remains the screening test of choice and should be offered to all average-risk adults aged 50 years or older. However, screening should begin at age 45 years in African Americans.
- The screening interval after normal colonoscopy result should be 10 years.
- It is also reasonable to consider screening at an age earlier than 50 years in patients with characteristics known to promote colorectal cancer, including a history of smoking and obesity.
- However, there is no formal recommendation for earlier screening in these subgroups of patients at this time.
- In patients with a single first-degree family member with colorectal cancer or advanced adenoma diagnosed at 60 years or older, the recommended screening protocol is unchanged from that of patients at average risk for colorectal cancer.
- However, if the colorectal cancer or advanced adenoma in the first-degree family member is diagnosed at younger than 60 years, or if there are 2 first-degree relatives with colorectal cancer or advanced adenoma, screening colonoscopy should begin at age 40 years, or 10 years younger than the age at diagnosis of the youngest affected relative.
- Colonoscopy should be repeated at 5-year intervals for these patients.
- Patients with familial adenomatous polyposis should undergo annual flexible sigmoidoscopy or colonoscopy until colectomy is performed.
- Another preferred screening test is annual FIT.
- Alternative and less-preferred screening tests for colorectal cancer include flexible sigmoidoscopy every 5 years, or computed tomographic colonography every 5 years. D
- Duble-contrast barium enema testing is no longer part of the screening recommendations for colorectal cancer. Its use has declined dramatically, and computed tomographic colonography is more effective in diagnosing polyps.
- Fecal DNA testing has yielded disappointing sensitivity as a screening test for colorectal cancer, but more advanced assays are in development. Fecal DNA testing plus annual Hemoccult SENSA is an alternative for colorectal cancer screening at 3-year intervals.