Comparing per-pass performance of 2 types of needles for EUS-guided fine-needle biopsy sampling of pancreatobiliary masses in a randomized trial

Abstract

Background and aims: EUS-guided fine-needle biopsy sampling (EUS-FNB) has largely replaced FNA for tissue diagnosis of pancreatobiliary mass lesions. However, the optimal number of passes required for the diagnosis of malignancy is not clear. We aimed to compare the per-pass performance of 2 types of fine-needle biopsy (FNB) needles for the detection of malignancy.

Methods: One hundred fourteen patients referred for EUS evaluation of solid pancreatobiliary mass lesions underwent randomization between biopsy sampling with a Franseen needle and a 3-prong tip needle with an asymmetric cutting surfaces. Four passes of EUS-FNB were taken from each mass lesion. Two pathologists blinded to needle type analyzed the specimens. The final diagnosis of malignancy was made based on FNB specimen pathology, surgery, or a follow-up of at least 6 months after EUS-FNB. The sensitivity of EUS-FNB to diagnose malignancy was compared between the 2 groups. The cumulative sensitivity of detection of malignancy by EUS-FNB was calculated after each pass in each arm. Other characteristics of the specimens including cellularity and blood contents were also compared between the 2 groups. In the primary analysis, lesions categorized as suspicious on EUS-FNB were considered nondiagnostic for malignancy.

Results: Ninety-eight patients (86%) had a final diagnosis of malignancy, and 16 patients (14%) had benign disease. Four passes of EUS-FNB with the Franseen needle detected malignancy in 44 of 47 patients (sensitivity, 93.6%; 95% confidence interval [CI], 82.5-98.7) and with the 3-prong asymmetric-tip needle in 50 of 51 patients (sensitivity, 98%; 95% CI, 89.6-99.9; P = .35). Two passes of EUS-FNB detected malignancy with a sensitivity of 91.5% (95% CI, 79.6-97.6) with the Franseen needle and 90.2% (95% CI, 78.6-96.7) with the 3-prong asymmetric-tip needle. The cumulative sensitivities at pass 3 were 93.6% (95% CI, 82.5-98.6) and 96.1% (95% CI, 86.5-99.5), respectively. Samples collected with the Franseen needle had significantly higher cellularity than samples collected with the 3-prong asymmetric-tip needle (P < .01). However, no difference as found between the 2 types of needles in term of specimen bloodiness.

Conclusions: No significant differences were found in the diagnostic performance of the Franseen needle versus the 3-prong asymmetric-tip needle in patients with suspected pancreatobiliary cancer. However, the Franseen needle yielded higher cellularity of the specimen. Two passes of EUS-FNB are required to detect malignancy with at least 90% sensitivity with either type of needle. (Clinical trial registration number: NCT04975620.).