Gastric Metastasis from Clear Cell Renal Cell Carcinoma Presenting with Gastrointestinal Bleeding: A Case Report

Abstract

Introduction: Renal cell carcinoma (RCC) is the most common cancer originating from the kidney, it is responsible for 80 to 85 % of all primary renal neoplasms. The most common sites of metastasis include lungs, bones, liver, and brain. However, Gastric metastases from RCC are exceedingly. Hematogenous metastases to the stomach in general are rare with incidence in autopsy 0.2-9%. Breast cancer, malignant melanoma and lung cancer as the most common cancers metastasizing to the stomach. There are only few cases in literature of RCC gastric metastasis, most of them are of clear cell type. It can be diagnosed even many years after removal of the primary cancer which indicates slow growing potential. Case report: 67-year-old male patient with past medical history of polycystic kidney disease, live donor renal transplant in 2002, and metastatic left sided renal cell carcinoma treated with radical nephrectomy and resection of pulmonary metastasis in 2014. He presented with multiple episodes of black tarry stool for the last 2 days. He was on aspirin and ticagrelor. Initial laboratory workup showed Hemoglobin 8.8 g/dl; platelet count 344*1000/cmm; and INR 1.2. The patient was admitted for stabilization and further evaluation of gastrointestinal bleeding. The patient was started on pantoprazole infusion and ordered 2 units of PRBCs. His aspirin and ticagrelor were held. Esophagogastroduodenoscopy (EGD) showed a 2.5 to 3.0 cm polypoid mass in the gastric fundus. The polyp was 90% removed with a polypectomy snare and cautery. Bleeding occurred after the procedure and hemostasis was achieved by local epinephrine injection, and application two Cook hemostasis clips. Histologic examination demonstrates tumor composed of nests and fascicles of cells with abundant clear cytoplasm and moderately pleomorphic nuclei with prominent eosinophilic nucleoli. Immunohistochemical staining was most consistent with metastatic clear cell renal cell carcinoma, and it was comparable with right lung biopsy resected in 2014.Figure 1Conclusion: Gastric involvement in renal cell carcinoma is rare even-though it's reported. The possibility of gastrointestinal involvement should always be considered in any patient with history of cancer who presents with gastrointestinal symptoms. Immunohistochemistry is also very useful in the diagnostic workup and in many cases it is possible to make a diagnosis in the absence of access to the primary tumor.Figure 2