Endoscopic ultrasound-guided tissue acquisition by 22-gauge franseen and standard needles for solid pancreatic lesions

Background/Aims: Recently, a three-plane symmetric needle with Franseen geometry was developed for endoscopic ultrasound-guided fine needle biopsy (EUS-FNB). In this retrospective study, tissue acquisition per pass was compared between 22-gauge Franseen FNB and standard fine needle aspiration (FNA) needles in patients with solid pancreatic lesions. Methods: Consecutive patients who underwent EUS-FNA or EUS-FNB for solid pancreatic lesions between October 2014 and March 2018 were retrospectively studied. The tissue acquisition rate and the diagnostic performance per session, per pass, and at first pass were compared. Results: A total of 663 passes (300 by the FNB needle and 363 by the standard FNA needle) were performed in 154 patients (71 FNB and 83 FNA). The tissue acquisition rate per session and at first pass in the FNB and FNA groups was 100% and 95% (p=0.13) and 87% and 69% (p=0.007), respectively. The multivariate analysis revealed that among the patients, EUS-FNB (odds ratio, 3.07; p=0.01) was associated with a higher first-pass tissue acquisition rate. While the tissue acquisition rate reached a plateau after the 4th pass with FNA, it reached a plateau after the 2nd pass with FNB. Among the 129 malignant cases, the histological tissue acquisition rate per session was similar (100% and 94%), but the sensitivity by histology alone per session was higher for FNB than for FNA (93% and 73%, p<0.01). Conclusions: The results of our retrospective analysis indicated that compared with a standard FNA needle, a 22-gauge Franseen FNB needle was associated with a higher first-pass tissue acquisition rate.