Endoscopic ultrasound–guided fine-needle biopsy (EUS-FNB) is the recommended method for tissue acquisition in suspected pancreatic cancer. Third-generation biopsy needles provide improved histologic yield; however, the optimal sampling technique—particularly the use of suction—remains unclear. This prospective study compared suction versus no-suction sampling during EUS-FNB of solid pancreatic lesions using a Franseen-tip needle.

In a tertiary center, 88 consecutive patients with pancreatic solid lesions highly suggestive of malignancy on cross-sectional imaging were enrolled. All underwent EUS-FNB using a 22-gauge Franseen needle. Patients were randomized to an aspiration technique (stylet removal and 20-ml negative suction) or a non-aspiration technique (NAT, no application of negative pressure). Macroscopic on-site evaluation guided the number of needle passes. A single blinded gastrointestinal pathologist assessed tissue integrity, blood contamination, and final histopathologic diagnosis. The primary endpoint was diagnostic accuracy for pancreatic cancer.

46 procedures were performed using NAT and 42 using the aspiration technique. Demographic characteristics were comparable between groups. Non-aspiration sampling yielded significantly less blood contamination (39.1% vs 64.2%, p<0.05). Diagnostic confirmation of adenocarcinoma was higher in the non-aspiration group (95.6% vs 88%). Negative results occurred only in the aspiration group (12%). Indeterminate samples were noted in the NAT group (4.4%). The number of needle passes did not differ significantly (1.39 vs 1.25, p=0.228).

EUS-FNB without suction resulted in higher diagnostic accuracy and lower blood contamination compared with suction-assisted sampling. Avoiding suction may optimize tissue quality when using a Franseen-tip needle for solid pancreatic lesions.