Comparative study of diagnostic value of cytologic sampling by endoscopic ultrasonography-guided fine-needle aspiration and that by endoscopic retrograde pancreatography for the management of pancreatic mass without biliary stricture

Background: Endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) can now provide a cytopathological diagnosis of underlying pancreatic malignancy with higher success rates than endoscopic retrograde pancreatography (ERP). To determine the significance of EUS-FNA for the diagnosis of pancreatic mass without biliary stricture, the value of cytopathological diagnosis obtained by EUS-FNA was retrospectively compared with that by ERP, and the complications associated with these procedures evaluated. Methods: Eighty-three patients who were suspected to have a pancreatic mass (excluding a cystic mass), without biliary stricture on conventional ultrasound and/or computed tomography were enrolled. The EUS-FNA biopsy was performed in 53 patients and cytology utilizing ERP was performed in 30 patients. Results: The sampling rate of adequate specimen was 100% in both groups. In the EUS-FNA group, the overall results for the available samples were sensitivity 92.9% and accuracy 94.3%. In contrast, in the ERCP group, the overall results were sensitivity 33.3% and accuracy 46.7%. There was a significant difference between the two groups (P < 0.01). With regard to complications, there was a significant difference (P < 0.01) in the frequency of post-procedure pancreatitis between the EUS-FNA group and ERP group (0%, 0/53 vs 33.3%, 10/30, respectively). Conclusion: Endoscopic ultrasonography-guided fine-needle aspiration is safer and more accurate for the cytopathological diagnosis of suspected pancreatic masses without a biliary stricture as compared with cytology during ERP. Endoscopic ultrasonography with FNA should be considered a preferred test (prior to attempting endoscopic retrograde cholangiopancreatography) when a cytological diagnosis of a pancreatic mass is required, especially when there is no biliary obstruction, or when emergent decompression of an obstructed biliary tree is not considered clinically necessary due to lack of signs and symptoms of cholangitis.