Serous Cystadenoma of the Pancreas with Endoscopic Ultrasound Fine Needle Aspiration Biopsy and Surgical CorrelationCollins B.T.
Department of Pathology and Immunology, School of Medicine, Washington University in St. Louis, St. Louis, Mo., USA
Objectives: Endoscopic ultrasound (EUS) fine needle aspiration (FNA) biopsies are commonly used to diagnose tumors of the pancreas. Serous cystadenoma (SCA) is a benign neoplasm that is uncommon and accounts for 1-2% of all pancreatic neoplasms. Study Design: Surgically excised SCAs with preoperative EUS FNA biopsy over a 10-year span were identified. Clinical data were collected, and cytomorphologic features reviewed retrospectively and correlated with surgical excision data. Original cytopathologic diagnoses and retrospectively reviewed cytomorphology features were recorded. Results: Seventeen patients were identified. Original EUS FNA interpretation included 1 ‘unsatisfactory', 9 ‘negative for malignancy' and 7 ‘atypical' or greater; however, all cases were categorized as benign/negative or nondiagnostic on retrospective review. The cases were hypocellular and possessed variable (rare to few-moderate) groups of bland cuboidal epithelial cells embedded in granular debris. Mucosal sampling was present (7/17) and cell blocks were acellular (5/17). Conclusion: This is a large series of pancreas SCAs subjected exclusively to EUS FNA biopsy where all cases had surgical excision confirmation. The 17 cases had hypocellular aspirate smears with the majority showing few bland epithelial cells; however, this can limit definitive diagnosis based on the cytomorphologic evaluation alone. The aspirate smear pattern of EUS FNA of SCAs of the pancreas supports a benign/negative or nondiagnostic categorization.