For an individual with a first-degree relative who has colon cancer, what is the initial colorectal cancer screening recommendation?

• A. 40 year old with a parental history of Crohn's disease
• B. 40 year old with a parental history of diverticular disease
• C. 40 year old with a parental history of colon cancer
• D. 40 year old with a parental history of irritable bowel syndrome

Answer: (C)

Having a first-degree relative with colon cancer raises your risk and justifies starting screening earlier than average risk. The best initial test is colonoscopy because it not only detects cancer but also allows removal of polyps in the same procedure, reducing future risk.

For someone with one affected first-degree relative, screening should begin at age 40 or 10 years younger than the earliest diagnosis in the family, whichever comes first. If the relative was diagnosed before age 60, follow-up colonoscopies are every 5 years; if diagnosed at 60 or older, every 10 years. In this scenario, a 40-year-old with a parent who had colon cancer meets the starting point, so the initial recommendation is to schedule a colonoscopy now. The other parental histories described do not necessitate starting screening at this age for colon cancer in the same way.