Case of the Month: September 2025

Clinical history

A 79-year-old female with a past medical history including hypertension, dyslipidemia and prior stroke presents with a history of chronic fatigue. She denies fevers, weight loss, night sweats, bowel habit changes or blood per rectum. Blood work demonstrates a normocytic anemia. White blood cell count, platelets, INR and PTT are within normal limits. A CT scan and subsequent colonoscopy demonstrated a friable mass in the cecum. The mass was biopsied on colonoscopy, and she was scheduled to undergo a right hemicolectomy.

Questions:

1. Provide a differential for lower GI bleeding in an adult. Of your differential, which is the most likely diagnosis?
2. What immunohistochemical stains or additional studies might be done in this case and why?
3. What features of this entity might provide prognostic information for this patient?

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