PAEA Surgery End Of Rotation (EOR) Practice Exam

Where do 40-50% of GI carcinoids typically originate?

1. The stomach

2. The colon

3. The appendix

4. The ileum

The correct answer is: The appendix

GI carcinoids, which are neuroendocrine tumors, predominantly originate from enterochromaffin cells located throughout the gastrointestinal tract. While carcinoid tumors can arise in various parts of the GI system, approximately 40-50% originate in the appendix. This high frequency can be attributed to the unique characteristics of the appendix, including its rich supply of enterochromaffin cells and the lymphatic drainage that favors the development of carcinoid tumors. This emphasis on the appendix as a frequent site for carcinoids is crucial for clinicians as it impacts diagnosis, treatment strategies, and surveillance guidelines for potential metastasis or recurrence, especially considering that carcinoids originating in the appendix may differ in behavior and prognosis compared to those from other sites like the ileum or colon. Thus, robust knowledge of the origin and characteristics of these tumors is essential for effective management and patient outcomes.