Comparison of Diagnostic Efficacy and Safety between 22-gauge Aspiration and Biopsy Needles for EUS-guided Sampling of Pancreatic Solid Lesions

Abstract

Introduction: The advantage of EUS-guided fine needle biopsy (EUS-FNB) over fine needle aspiration (EUS-FNA) is that it allows the acquisition of histologic core tissues. We conducted this study to compare diagnostic efficacy and safety of the new 22-gauge core biopsy needle to those of FNA needle for diagnosis of pancreatic solid lesions in the absence of on-site cytopathologists. Methods: The Patients who underwent EUS-FNA or FNB between September 2011 and December 2012 were reviewed retrospectively. Among them we enrolled patients who underwent the procedure for diagnosis of pancreatic solid lesion using 22-gauge needle. Diagnostic efficacy and safety were compared between FNA and FNB group. In addition, we analyzed whether the diagnostic yields of EUS-FNA and FNB vary according to the final diagnosis. Results: A total of 148 patients were enrolled (73 FNA and 75 FNB). Two groups showed comparable diagnosis achievement rates (75.3 vs 84.0%, P=0.19), and no severe complication occurred. There were 128 pancreatic cancer (86.5%), 12 neuroendocrine tumor (8.1%), 4 autoimmune pancreatitis (2.7%), and 3 idiopathic pancreatitis (2.0%). In pancreatic cancer patients 68 FNA and 60 FNB were performed. Sensitivities of FNA and FNB were 75.0% and 85.0%, and there was no statistically significant difference (P=0.19). The sensitivity of EUS-FNA was similar to that of EUS-FNB in transduodenal puncture (73.9 vs 70.6%, P=1.0). In contrast, the sensitivity of EUS-FNA tended to be lower than that of EUS-FNB in transgastric puncture (75.6 vs 90.7%, P=0.06). Specificities were 100% in both groups. A total of 12 neuroendocrine tumor (NET) patients were included (3 FNA and 9 FNB). All patients were diagnosed as NET except a patient in the FNB group. Ki-67 index was measured in 5 patients of the FNB group, and it provided crucial information for the management of patients. FNB was performed for 3 autoimmune pancreatitis (AIP) patients, and it enabled histologic diagnosis of AIP for one of them. Conclusions: In the absence of on-site cytopathologists, EUS-FNB is comparable to FNA for the diagnosis of pancreatic cancer, however FNB might be preferred to FNA when transgastric puncture is performed. EUS-FNB can be helpful in the diagnosis and management of NET and AIP.