Metastatic renal cell carcinoma to the small bowel: three cases of GI bleeding and a literature review

Abstract

Approximately 25-30% of patients with renal cell carcinoma (RCC) have metastatic disease at the time of diagnosis, where the most common sites of metastasis are the lung (50-60% of patients with metastatic disease), bones (30-40%), liver (30-40%), and brain (5%). Although RCC metastasis to the small intestine is thought to be exceedingly rare, with predominantly isolated case reports and a few case series in the literature, we present below three additional cases at our institution of metastatic RCC to the small bowel presenting as GI bleeding. A literature review demonstrates that the number of published case reports has been increasing in recent years. We hypothesize that in the era of targeted chemotherapy and VEGF inhibitors to treat RCC that patients are living longer and have more time for their primary tumors to metastasize to the small bowel and become symptomatic, causing metastatic RCC to the small bowel to be less rare than previously thought.Copyright © 2017, Japanese Society of Nephrology.