Metastatic spindle-cell renal carcinoma presenting as multiple intestinal polyps.

A 75-year-old woman presented with rapidly progressive intestinal and general symptoms including diarrhea, melena, weight loss, back pain, and lassitude. Endoscopy revealed multiple intestinal polyps which, microscopically, consisted of metastatic tumor deposits composed predominantly of spindle-shaped tumor cells. The primary tumor, a mixed spindle-cell and clear-cell carcinoma, was later identified in the kidney at autopsy. The patient had a cholecystectomy 13 years previously.