2033 Gastrointestinal Bleeding: A Rare Manifestation of Renal Cell Carcinoma

Abstract

INTRODUCTION: We describe a rare cause of gastrointestinal bleeding in a patient with metastatic renal cell carcinoma (RCC) and discuss consideration and workup of this manifestation, as it is becoming more common given improved survival of this patient cohort. CASE DESCRIPTION/METHODS: A 65-year-old male with history of RCC treated with left nephrectomy complicated by local recurrence and pancreatic tail involvement, on nivolumab, presented with melena and dyspnea. Vitals were notable for orthostasis, melena on rectal exam, and labs revealed a Hgb of 5.6 gm/dL. After resuscitation, the patient underwent push enteroscopy and colonoscopy which did not reveal a source. The following day, the patient developed large volume hematochezia with lightheadedness, hypotension, and acute blood loss anemia requiring transfusion. Given his negative endoscopy and known metastatic RCC, CT angiogram was performed demonstrating an enhancing left upper quadrant soft tissue mass invading into the small bowel lumen. Interventional Radiology was consulted and recommended against embolization due to high risk of small bowel necrosis. Subsequently, Surgery was consulted and requested video capsule endoscopy, but the patient deteriorated requiring emergent surgery. An ileal mass, confirmed to be metastatic RCC, was resected. The patient had no further bleeding and was discharged home; he continues to follow closely with Oncology. DISCUSSION: Metastases to the small bowel are a rare cause of GI bleeding, but are often due to malignancies of the breast, cervix, lung, and melanoma. RCC metastatic to the small bowel has only been described in case reports thus far, but may become more common. Advances in targeted chemotherapeutics of the VEGF and mTOR pathways lead to improved survival and thus, more opportunities for metastases. Patients may present with intussusception, bowel obstruction, or GI bleeding alone, with bleeding favored by their vascular nature. Patients will undergo extensive upper and lower endoscopic evaluation without localizing the source, prompting cross-sectional imaging which is more sensitive for confirming the diagnosis. Surgery is often required, as tumors supplied by branches of the mesenteric arteries pose significant risk of small bowel infarction if embolized. In patients with known history of RCC who present with GI bleeding, small bowel metastases should be considered as an etiology if endocscopy is negative, and obtaining CT imaging urgently may lead to timely management of such lesions.