Sigmoid Colonic Polyp as Initial Presentation of Metastatic Papillary Renal Cell Carcinoma.

Background: Upon initial presentation, 25%-30% of patients with renal cell carcinoma have metastatic disease. Metastasis to the gastrointestinal tract is rare, but when it occurs, the large bowel is the least common site.

Case Report: A 75-year-old white male presented with vague abdominal symptoms and worsening hemoglobin and hematocrit levels. Colonoscopy revealed a polyp in the distal portion of the sigmoid colon. Histologic and immunohistochemical analysis suggested metastatic papillary renal cell carcinoma.

Conclusion: To the best of our knowledge, this patient had a rare case of metastatic papillary renal cell carcinoma that metastasized to the colon and presented as a colon polyp.