Metastatic Renal Cell Carcinoma to the Pancreas: Diagnostic Significance of Fine-Needle Aspiration Cytology

Background: Renal cell carcinoma rarely metastasizes to the pancreas. Diagnosing a neoplasm that is metastatic to the pancreas by fine-needle aspiration (FNA) cytology is often challenging. A detailed clinical history may prove to be beneficial. Case Reports: A total of 729 pancreatic FNAs were performed from January 2005 through August 2012 at our institution. Among these, we found 3 patients with a prior history of a malignant renal neoplasm who presented with a pancreatic mass: 2 in the tail and 1 in the head. Radiographically, they ranged in size from 2.5 to 7.0 cm. Microscopic evaluation of cytologic material obtained during endoscopic ultrasound-guided FNA (EUS-FNA) revealed cohesive clusters of atypical cells with clear cytoplasm and prominent nucleoli surrounded by a thin capillary network. The neoplastic cells were immunoreactive with CD10 (cases 2 and 3). A diagnosis of metastatic clear cell renal cell carcinoma was rendered for each case based on the morphologic features and immunohistochemical staining pattern of the neoplastic cells. Histologic comparison with the available slides of the corresponding primary renal neoplasm confirmed the diagnosis. Conclusion: We conclude that EUS-FNA of pancreatic masses is an important, effective, and accurate diagnostic modality for early diagnosis of both primary and metastatic neoplasms of the pancreas. Copyright (C) 2013 S. Karger AG, Basel