Addition of endoscopic ultrasound (EUS)-guided fine needle aspiration and on-site cytology to EUS-guided fine needle biopsy increases procedure time but not diagnostic accuracy

Background/Aims: Although the diagnostic accuracy of endoscopic ultrasound with fine needle aspiration (EUS-FNA) in pancreas adenocarcinoma is high, endoscopic ultrasound with fine needle biopsy (EUS-FNB) is often required in other lesions; in these cases, it may be possible to forgo initial EUS-FNA and rapid on-site cytology evaluation (ROSE). The aim of this study was to compare the diagnostic accuracy of EUS-FNB alone (EUS-FNB group) with a conventional sampling algorithm of EUS-FNA with ROSE followed by EUS-FNB (EUS-FNA/B group) in nonpancreas adenocarcinoma lesions. Methods: Retrospective cohort study of subjects who underwent EUS sampling of nonpancreatic adenocarcinoma lesions between February 2011 and May 2013. Results: Over the study period, there were 43 lesions biopsied in 41 unique patients in the EUS-FNB group and 53 patients in the EUSFNA/ B group. Overall diagnostic accuracy was similar between the EUS-FNB and EUS-FNA/B groups (83.7% vs. 84.9%; p=1.0). In the subgroup of subepithelial mass lesions, diagnostic accuracy remained similar in the EUS-FNB and EUS-FNA/B groups (81.0% and 70.6%; p=0.7). EUS-FNB procedures were significantly shorter than those in the EUS-FNA/B group (58.4 minutes vs. 73.5 minutes; p<0.0001). Conclusions: EUS-FNB without on-site cytology provides a high diagnostic accuracy in nonpancreas adenocarcinoma lesions. There appears to be no additive benefit with initial EUS-FNA but this requires further study in a prospective study.