Stylet Slow-pull Versus Standard Suction for Endoscopic Ultrasound-guided Fine-needle Aspiration/Biopsy of Pancreatic Solid Masses: A Meta-Analysis.

Background And Study Aim: There is limited evidence on the diagnostic performance of the stylet slow-pull (SP) method for endoscopic ultrasound-guided fine-needle aspiration/biopsy. The aim of this study was to compare the SP method with standard suction (SS) for endoscopic ultrasound-guided fine-needle aspiration/biopsy of solid pancreatic masses.

Methods: A computerized bibliographic search of the main databases, including PubMed, EMBASE, Cochrane Library, and Science Citation Index, was performed through February 2020. The main outcome measurements were diagnostic accuracy, cellularity, low blood contamination, adequate core tissue acquisition, and technical success rate.

Results: Eleven studies (including 6 randomized trials) were included, with a total of 504 patients who underwent SP and 551 who underwent SS. Diagnostic accuracy was significantly superior in the SP group, compared with the SS group [odds ratio (OR)=1.60; 95% confidence interval (CI), 1.14-2.26]. The SP group had higher pooled rates of low blood contamination (OR=1.93; 95% CI, 1.29-2.87) and adequate core tissue acquisition (OR=1.91; 95% CI, 1.11-3.26) than the SS group. There was no significant difference between groups in the adequacy of cellularity (OR=0.99; 95% CI, 0.63-1.57; P=0.98) or technical success rate (OR=0.38; 95% CI, 0.13-1.15; P=0.09).

Conclusions: The authors provide evidence that SP is superior to SS in diagnostic accuracy, low blood contamination, and adequate core tissue acquisition, without reducing adequacy of cellularity or technical success rate.