American Board of Internal Medicine (ABIM) Certification Practice Exam

Which of the following is a recommendation for colorectal cancer screening based on family history?

1. Begin screening at age 50 for any relative with colon cancer

2. Start at age 40 or 10 years before the earliest case in the family

3. Screen every 10 years if there's no family history

4. Only screen those with a family history of rectal cancer

The correct answer is: Start at age 40 or 10 years before the earliest case in the family

The recommendation to start screening for colorectal cancer at age 40 or 10 years before the earliest case in the family is based on the understanding that individuals with a family history of colorectal cancer are at a higher risk for developing the disease. Recognizing that genetic predispositions play a significant role in cancer risk, this guideline provides an appropriate approach to identify potential cancers at an earlier age for those at risk. This method is particularly useful as it adjusts the screening age not just by a standard age but tailors it to the family history, considering when family members were diagnosed, which can indicate heightened risk. For example, if a family member was diagnosed at 45, starting screening at 35 years of age (10 years earlier) allows for timely detection and intervention. Other choices do not appropriately address the considerations of family history. The recommendation to begin screening at age 50 for any relative with colon cancer does not take into account the increased risk factors tied to specific familial history. Similarly, a recommendation to screen every 10 years without any family history overlooks the importance of earlier and more frequent screenings for those with familial links. Lastly, only screening those with a family history of rectal cancer limits the understanding of colorectal cancer risk, which also includes colon cancer