This observational study compared quality of histological sampling of pancreatic EUS-FNB with the 20-gauge Procore® and 22-gauge Acquire® needles. In total, 68 patients were recruited. Histological diagnosis was achieved and a histological core biopsy was obtained in 82% of patients (28/34) in the 20-gauge Procore® group and 97% of patients (33/34) in the 22-gauge Acquire® group (P=0.1). Core biopsy specimens obtained were significantly longer with the 22-gauge Acquire® needle with a mean cumulative length of tissue core biopsies per needle pass of 4,33±3,46mm vs. 7,9±4,35mm for the 20-gauge Procore® (P<0,01). Reproducibility of this simple histological criterion was validated in intra and inter-observer.

Between March and December 2017, 68 EUS-FNB were consecutively performed in our unit for a pancreatic or peripancreatic mass. The choice of the needle depended upon the availability at the time of admission: 34 punctures were performed with a 20-gauge Procore®, and 34 with a 22-gauge Acquire®. Histological material was studied in a blinded manner with respect to the needle, and cumulative length of tissue core biopsies per needle pass was determined. Intra and inter-observer variability of this criterion was then evaluated.

Inclusion Criteria:

• All consecutive patients ≥18 who were referred for EUS-FNB for solid pancreatic or peripancreatic mass were included

Exclusion Criteria:

• non-accessible pancreatic mass because of history of Billroth II or Roux-en-Y reconstruction
• coagulation disorders (such as partial thromboplastin time >42 seconds, prothrombin time [Quick value] <50%, platelet count <50 000/mm³), treatment with clopidogrel, pregnancy.
• patients <18 years of age

All consecutive patients ≥18 who were referred for EUS-FNB for solid pancreatic or peripancreatic mass were included. The use of EUS-FNB needle was determined during EUS if the examination confirmed the presence of a pancreatic or peri-pancreatic non-hyper-vascular mass (on Doppler examination).

According to the period of admission, the 20-gauge Procore® (Wilson Cook Medical, Winston-Salem, NC) and 22-gauge Acquire® needles (Boston Scientific Natick, MA) were alternatively available depending on the order (made in batches of 5 units). So, patients were included either in the 20-gauge Procore® group or the 22-gauge Acquire® group.

Patients could be switched via a crossover procedure to a second EUS-FNB with the competitive needle if the first one failed to give histologic mass characterization: failure was recorded to the first needle group, and the second EUS-FNB performed with the alternate needle was recorded in the other group.