EUS-guided fine-needle biopsy sampling of solid pancreatic tumors with 3 versus 12 to-and-fro movements: a multicenter prospective randomized controlled study

Background and aims: A novel EUS-guided fine-needle biopsy sampling (EUS-FNB) needle enabled physicians to obtain sufficient pathologic samples with fewer to-and-fro movements (TAFs) within the lesion. We compared the diagnostic yields of EUS-FNB with 3 and 12 TAFs at each puncture pass.

Methods: The primary endpoint of this multicenter, noninferiority, crossover, randomized controlled trial involving 6 centers was diagnostic sensitivity. Secondary endpoints were diagnostic accuracy and quantity and quality evaluation of EUS-FNB specimens. Length of the macroscopically visible core (MVC) and microscopic histologic quantity were used for quantitative evaluation. Macroscopic visual and microscopic histologic evaluations were performed for qualitative evaluation.

Results: Among 110 patients (220 punctures, 110 for 3 TAFs and 12 TAFs each), 105 (210 punctures) had malignant histology. Diagnostic sensitivity for malignancy of 3 TAFs (88.6%) was not inferior to that of 12 TAFs (89.5%; difference, -.9%; 95% confidence interval, -9.81 to 7.86). Diagnostic accuracy for malignancy was 92.7% for 3 TAFs and 94.6% for 12 TAFs. Overall median MVC length was 13.5 mm in both groups. The 3-TAF group had a significantly higher rate of score ≥3 on macroscopic visual quality evaluation than the 12-TAF group (71.8% vs 52.7%, P = .009). No significant intergroup differences existed in microscopic histologic quantity and quality evaluations (quantity evaluation, 88.2% for 3 TAFs vs 83.6% for 12 TAFs; quality evaluation, 90.0% for 3 TAFs vs 89.1% for 12 TAFs).

Conclusions: Diagnostic sensitivity and accuracy of EUS-FNB with 3 TAFs were not inferior to those with 12 TAFs for solid pancreatic lesions. The 3-TAF group showed significantly less blood contamination in sampled tissues than the 12-TAF group. (Clinical trial registration number: UMIN000037309.).