American Board of Internal Medicine (ABIM) Certification Practice Exam

What is one method for screening colon cancer in patients at average risk?

1. Annual FOBT

2. Only colonoscopy

3. CT colonography every 2 years

4. Flexible sigmoidoscopy once

The correct answer is: Annual FOBT

Screening for colon cancer in patients at average risk is an important preventive measure, and one widely accepted method is the annual fecal occult blood test (FOBT). This test is designed to detect hidden blood in the stool, which can be an early sign of colorectal cancer or advanced adenomatous polyps. The FOBT is non-invasive, easy to administer, and effective as a preliminary screening tool. Following a positive result from an FOBT, further diagnostic procedures like colonoscopy may be recommended for confirmation and to evaluate for any cancerous lesions. This approach facilitates early detection of colorectal cancer, significantly improving treatment outcomes and survival rates. Other methods, such as colonoscopy, while being a gold standard, require more extensive preparation and are not done annually for average-risk individuals, since screening intervals typically extend to every 10 years. CT colonography, although useful, is typically recommended every 5 years, not annually. Flexible sigmoidoscopy, while a valid screening option, is generally performed at longer intervals compared to the FOBT schedule. Thus, annual FOBT is a recommended and effective option for average-risk individuals in a screening regimen.