OBJECTIVE: Data on adequacy of EUS guided biopsies using different tissue acquisition techniques and fine needle aspiration needle designs have been inconclusive. Data on newer fine needle biopsy (FNB) needles are scarce. This study compared the performance of 3 acquisition techniques and 2 fine needle biopsy designs in solid pancreatic lesions.
METHODS: Single-center, randomized, pilot clinical trial (Trial registration number NCT03264092). Patients undergoing EUS biopsy of pancreatic lesions were randomized to 1 of 3 acquisition techniques (dry suction, wet suction, slow pull) and 1 of 2 22G FNB needle designs. The primary outcome was specimen cellularity. Secondary outcomes included blood contamination and number of passes needed for diagnosis.
RESULTS: A total of 52 (35.3%), 49 (33.3%) and 46 (31.3%) specimens were obtained with slow pull, dry suction and wet suction, respectively. A total of 56 (38%) and 91 (62%) specimens were obtained with each needle, respectively. No difference in cellularity scores was identified by technique (3.28 vs 3.55 vs 2.94; p = 0.081) or needle type (3.45 vs 3.15; p = 0.19). The same was true for blood contamination and diagnostic pass. A diagnosis was reached after 3 passes in 51 patients (93%). Histological diagnosis was possible in 45 specimens (82%). No severe adverse events occurred.
CONCLUSIONS: Cellularity of pancreatic specimens obtained with FNB needles via EUS was not influenced by technique and needle design. Three passes were enough to obtain a histological diagnosis in most patients. Larger clinical trials are required to validate the results of this study.

BACKGROUND: The effects of the Franseen needle size in endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) of solid pancreatic masses remain unclear. This study aimed to compare 25G and 22G Franseen needles in terms of adequate tissue acquisition from solid pancreatic masses.
METHODS: In this single-center, crossover, randomized noninferiority trial, eligible patients underwent EUS-FNB with both 25G and 22G Franseen needles in a randomized order between November 2018 and August 2020. Tissue specimens from each pass were separately evaluated based on the cellularity scoring system. The primary outcome was the proportion of acquired specimens allowing adequate histological assessment (cellularity score ≥3). A -15% noninferiority margin was assumed.
RESULTS: Data from 88 patients were analyzed, which showed malignant and benign lesions in 84 (95.5%) and four (4.5%) patients, respectively. Of the 88 specimens, 62 (70.5%) and 69 (78.4%) acquired using 25G and 22G needles, respectively, allowed adequate histological assessment. The adjusted proportion difference was -6.6% (95% confidence interval -8.8% to -4.5%), indicating noninferiority of the 25G Franseen needle (P < 0.001). The diagnostic accuracies of the 25G and 22G needles were 86.4% and 89.8%, respectively, with no significant difference (P = 0.180). Adverse events occurred in one patient.
CONCLUSIONS: The 25G Franseen needle showed a noninferior adequate tissue acquisition and similar diagnostic performance compared to that of the 22G Franseen needle. However, a 15% noninferiority margin was high for clinical use; thus, further consideration is needed (Clinical Trial Registry no. UMIN000034596).