A Rare Case of Synchronous Pancreatic Neuroendocrine Tumor and Renal Cell Carcinoma

Abstract

Purpose: A 64-year-old white female with history of diabetes, hypertension, and multiple abdominal surgeries presented with left upper quadrant abdominal pain, associated with nausea and vomiting. Physical exam revealed left upper quadrant tenderness. Labs revealed leukocytosis at 17.6. CT abdomen was concerning for small bowel obstruction and incidentally noted bilateral renal masses which were heterogeneously enhancing, and concerning for malignancy. A 2.1-cm cystic mass in the pancreatic body was also noted. The patient's small bowel obstruction resolved with conservative management. She then underwent CT-guided, right-sided renal mass biopsy, with pathology revealing renal cell carcinoma (RCC), clear cell type. Later EUS was performed, which identified a 2.7 x 2.3 cm cystic lesion in the pancreatic body. FNA was performed which was positive for Cam 5.2, synaptophysin, and chromogranin, consistent with a well-differentiated neuroendocrine tumor (NET). Immunostaining for RCC was negative, and Ki-67 proliferation index was less than 2%. Subsequently, somatostatin receptor scintigraphy (SRS) scan was obtained, and was normal. Serum chromogranin was borderline high at 6 nmol/L and serum gastrin was normal. Patient was then referred for possible partial nephrectomy and pancreatic tumor resection. Pancreatic NETs constitute about 2% of all gastrointestinal neoplasms. Secondary primary malignancies in these patients are a known entity, and their incidence is on the rise. We report a rare case of synchronous pancreatic NET and RCC. Physicians should be aware of the rising trend of synchronous tumors. Every effort should be made to further characterize the suspected lesions, as they are not always metastatic and treatment options may vary widely.