The slow-pull capillary technique increases the quality of endoscopic ultrasound fine needle biopsy samples in solid pancreatic lesions.

Abstract

Endoscopic ultrasound-guided sampling is used routinely for the diagnosis of solid pancreatic masses. We aimed to compare the standard suction technique with the recently described 'slow-pull' technique. Patients with a solid pancreatic mass of more than 2 cm undergoing endoscopic ultrasound-guided fine needle biopsy with the same endoscopist using a 22 G core biopsy needle were included in the study. Patients had a first suction pass, followed by either another suction pass or a slow-pull pass. The rate of samples contributive to the diagnosis, cellularity, presence of tissue microfragments, and blood contamination were assessed and compared between each pass and each technique. A total of 98 patients with a lesion diameter of 33.1±10 mm were analyzed. Lesions were adenocarcinomas in 83%, neuroendocrine tumors in 6%, and benign lesions in 11% of the cases. The rate of contributive samples of the first suction pass, the slow-pull pass, and the second suction pass were 96.9, 97.9, and 90.2%, respectively (P=NS). The slow-pull capillary technique, compared with the suction technique, provided samples with better cellularity, higher proportion of representative and tumor cells, and more tissue microfragments (P=0.002, 0.0004, 0.006, and 0.005, respectively). Endoscopic ultrasound-guided fine needle biopsy sampling of solid pancreatic lesions using the slow-pull technique yielded overall outcomes similar to the standard suction technique in terms of diagnostic performance. However, the slow-pull capillary technique improved the histological quality of the samples, mainly through a higher proportion of tissue microfragments and tumor cells.