A 5-year-old child of a parent with familial adenomatous polyposis (APC gene) is being screened. What is the most appropriate starting test and age?

A 5-year-old child of a parent with familial adenomatous polyposis (APC gene) is being screened. What is the most appropriate starting test and age?

• A. Colonoscopy starting at age 25
• B. Flexible sigmoidoscopy starting at age 10
• C. Annual CT colonography starting at age 15
• D. No screening until symptoms arise

Answer: (B)

In familial adenomatous polyposis, people who carry the APC mutation develop multiple polyps early, and cancer risk becomes near certain if not surveilled, so screening starts in childhood. The polyps typically begin in the rectum and sigmoid colon, making evaluation of the distal colon most efficient first. A flexible sigmoidoscopy can visualize that region, is less invasive for a child, and allows repeated annual surveillance to catch polyps early. If polyps are found, the next step is usually a full colonoscopy to map the extent and plan management, with colectomy considered as the polyp burden grows or cancer risk increases. Starting endoscopic surveillance at around age 10 aligns with guidelines for carriers and targets the region where polyps first appear, making it the best initial test and timing. Starting colonoscopy at age 25 is too late for this condition, annual CT colonography is not the standard pediatric surveillance modality due to radiation and practicality, and screening only after symptoms would miss the very high cancer risk in mutation carriers.

In familial adenomatous polyposis, people who carry the APC mutation develop multiple polyps early, and cancer risk becomes near certain if not surveilled, so screening starts in childhood. The polyps typically begin in the rectum and sigmoid colon, making evaluation of the distal colon most efficient first. A flexible sigmoidoscopy can visualize that region, is less invasive for a child, and allows repeated annual surveillance to catch polyps early. If polyps are found, the next step is usually a full colonoscopy to map the extent and plan management, with colectomy considered as the polyp burden grows or cancer risk increases.

Starting endoscopic surveillance at around age 10 aligns with guidelines for carriers and targets the region where polyps first appear, making it the best initial test and timing. Starting colonoscopy at age 25 is too late for this condition, annual CT colonography is not the standard pediatric surveillance modality due to radiation and practicality, and screening only after symptoms would miss the very high cancer risk in mutation carriers.