S2171 Renal Cell Carcinoma Metastatic to the Stomach: A Case Report

Abstract

INTRODUCTION: Renal cell carcinoma (RCC) accounts for 3% of cancer cases. About 25% are metastatic at time of diagnosis, most commonly to the lungs, brain, and bone. Metastatic RCC to the stomach is rare and can have several presentations, including as a solitary polyp, multiple polyps, or as ulcers, and are usually found in the submucosal layer. We present a case of GI bleeding in a male with known RCC found to have new mets to the stomach. CASE DESCRIPTION/METHODS: A 73yo WM with PMH of stage IV RCC with known mets to lung, bone, and brain, currently on bevacizumab and denosumab, who presented after an episode of hematemesis and melena. The patient had fatigue but denied any abdominal pain. His physical exam was benign with no hemodynamic instability. Admission labs were notable for hgb 7.1, down from 10 a week prior, plt 115, INR 1.1, BUN 43, creatinine 1.0. An EGD showed a 2cm clean based ulcerated mass in the cardia of the stomach (Figure 1). There were also several <1 cm, benign appearing, polyps in the body and antrum (Figure 2). EUS was performed prior to potential polypectomy to assess layer of origin and depth of invasion. EUS showed an isoechoic round mass arising from the mucosa. There was invasion into the muscularis mucosa but not submucosa. The mass was resected with snare. The tissue was sent to pathology and was consistent with RCC. The patient was discharged with outpatient follow up with oncology to discuss possible adjustments to his immunotherapy regimen. DISCUSSION: RCC is a rare cause of GI bleeding. In a study of 2082 patients with RCC, only 5 patients were found to have mets to the stomach. In this study it was found that even with RCC, a patient is still two times as likely to develop gastric cancer as they are a metastasis from RCC. While it is rare to have RCC mets to the stomach, it can be a poor prognostic sign. Almost all patients with RCC mets to the stomach have mets in other organs. Due to this, the diagnosis of a RCC met in the stomach, should prompt quick reimaging, and the patient needs to discuss with their oncologist about potential treatment modifications due to this poor prognostic sign. In terms of endoscopic findings, RCC can present as a wide variety of lesions, including ulcers, >1 cm polypoidal masses, <1 cm polyps, solitary, or multiples. They can also be mucosal or submucosal lesions. Due to this, it is important for both endoscopists and pathologists to keep RCC in the differential with most gastric polyps/ulcers even when they appear benign.Figure 1.: Ulcerated mass in the cardia of the stomach.Figure 2.: Subcentimeter gastric polyps.