Safety and efficacy of cytology brushings versus standard fine-needle aspiration in evaluating cystic pancreatic lesions: a controlled study

Background and study aims: Cystic pancreatic lesions (CPLs) are increasingly detected by various imaging studies. Mucinous CPLs carry a risk of malignant transformation but this is often difficult to diagnose preoperatively. In a previous report of 10 suspected mucinous CPLs, the cellular yield of endoscopic ultrasonography (EUS)-guided cytology brushings was found to be superior to the yield from standard fine-needle aspiration (FNA). The aim of this prospective and blinded study was to compare the cytology yield of mucinous epithelium from brushing with FNA in suspected mucinous CPLs. Patients and methods: In total, 37 patients with 39 CPLs measuring at least 20 mm were enrolled between June 2006 and July 2008 for EUS-cytobrushing and EUS-FNA of CPLs. Demographic, clinical, EUS, cytopathologic, and surgical data were recorded whenever available. Yield of cytology brushings was compared with that of FNA. Procedure morbidity was evaluated after 30 days. The main outcome assessed was yield of intracellular mucin (ICM) on cytobrushing specimens compared with EUS-FNA for the diagnosis of suspected mucinous CPL. Results: Cytobrushings were more likely to detect ICM than the EUS-FNA method (P = 0.001). In three patients with hypocellular FNA, dysplasia was found on cytology brushing and later confirmed by surgical pathology. Significant complications occurred in three patients (8%): one postbrushing bleeding and two acute pancreatitis. Conclusions: Cytology brushings are more likely to provide an adequate mucinous epithelium specimen than standard FNA and could aid the diagnosis of CPLs in a selective group of patients.