What are the next steps for a patient over 50 with a family history of colorectal cancer and a positive Fecal Occult Blood Test (FOBT) result?

Colonoscopy Within 60 Days is Mandatory

A patient with a positive FOBT must undergo complete colonoscopy within 60 days—repeating the stool test or using any other diagnostic modality is inappropriate and does not conform to expert recommendations. 1, 2

Immediate Next Steps

• Schedule colonoscopy immediately to examine the entire colon, as this is the only acceptable follow-up for any positive FOBT result 1
• Do not repeat the FOBT—this is a common error that delays diagnosis and does not conform to guidelines 1, 3
• Do not perform flexible sigmoidoscopy alone—colonoscopy is required because it was the diagnostic procedure used in mortality reduction trials and is substantially more accurate 1
• Avoid barium enema as an alternative, as colonoscopy is the gold standard for complete evaluation 1

Critical Timing Considerations

The patient's family history of colorectal cancer places them in a high-risk category requiring urgent evaluation 1:

• Target 60 days or less from positive test to colonoscopy completion 1
• The Veterans Health Administration policy sets a 60-day target specifically for this scenario 1
• Earlier evaluation may be warranted given the family history, which significantly increases cancer risk 1, 4

Why This Matters for Your Patient

This patient has two major risk factors working synergistically 1, 4:

• Age over 50 years: Standard screening age with increased baseline risk 1
• Family history of colorectal cancer: Particularly concerning if the affected relative was diagnosed before age 55 or if multiple family members are affected 4

The positive FOBT indicates approximately:

• 10% probability of colorectal cancer 4
• 37% probability of adenomatous polyps 4
• 33% combined probability of significant neoplasia requiring intervention 5

Common Pitfalls to Avoid

Physician-related errors account for 78% of failures to complete appropriate diagnostic evaluation 3:

• Do not repeat the FOBT (accounts for many physician-related failures) 3
• Do not perform sigmoidoscopy alone as a substitute for colonoscopy 3
• Do not delay or defer based on patient age alone unless life expectancy is less than 10 years 1
• Do not order upper endoscopy first—colonoscopy should be the initial procedure of choice for positive FOBT 6

Patient factors that commonly delay appropriate follow-up include 5:

• Insurance barriers (uninsured patients have 50% lower odds of completing colonoscopy) 5
• Age extremes (patients >80 or <50 years have lower completion rates) 5
• Recent prior colonoscopy within 5 years (68% lower odds of completion) 5

Ensuring Successful Completion

Gastroenterology consultation doubles the likelihood of completing appropriate follow-up (OR 1.99) 5:

• Refer directly to gastroenterology rather than managing through primary care alone 5
• Document the family history prominently in the referral to ensure appropriate risk stratification 1, 4
• Emphasize to the patient that this is not optional—colonoscopy is required regardless of symptoms 1, 2

What to Tell the Patient

• Any positive FOBT requires colonoscopy—there are no exceptions or alternatives 1, 2
• The test cannot be repeated to "confirm" the result—a single positive test is sufficient indication 1, 3
• Family history increases cancer risk, making timely evaluation even more critical 1, 4
• Colonoscopy will both diagnose and potentially treat any polyps found during the procedure 1

Post-Colonoscopy Surveillance

If colonoscopy reveals adenomatous polyps, regular surveillance colonoscopy will be necessary 4:

• Surveillance intervals depend on polyp characteristics (number, size, histology) 1
• Family history may shorten recommended surveillance intervals compared to average-risk patients 1