Fine Needle Biopsies of Solid Pancreatic Lesions: Tissue Acquisition Technique and Needle Design Do Not Impact Specimen Adequacy

Abstract

Background and aims: Data on adequacy of EUS guided biopsies using different tissue acquisition techniques and fine needle aspiration needle designs have been inconclusive. Data on newer fine needle biopsy (FNB) needles are scarce. This study compared the performance of 3 acquisition techniques and 2 fine needle biopsy designs in solid pancreatic lesions.

Methods: Single-center, randomized, pilot clinical trial (Trial registration number NCT03264092). Patients undergoing EUS biopsy of pancreatic lesions were randomized to 1 of 3 acquisition techniques (dry suction, wet suction, slow pull) and 1 of 2 22G FNB needle designs. The primary outcome was specimen cellularity. Secondary outcomes included blood contamination and number of passes needed for diagnosis.

Results: A total of 52 (35.3%), 49 (33.3%) and 46 (31.3%) specimens were obtained with slow pull, dry suction and wet suction, respectively. A total of 56 (38%) and 91 (62%) specimens were obtained with each needle, respectively. No difference in cellularity scores was identified by technique (3.28 vs 3.55 vs 2.94; p = 0.081) or needle type (3.45 vs 3.15; p = 0.19). The same was true for blood contamination and diagnostic pass. A diagnosis was reached after 3 passes in 51 patients (93%). Histological diagnosis was possible in 45 specimens (82%). No severe adverse events occurred.

Conclusions: Cellularity of pancreatic specimens obtained with FNB needles via EUS was not influenced by technique and needle design. Three passes were enough to obtain a histological diagnosis in most patients. Larger clinical trials are required to validate the results of this study.

Keywords: 22 G needles; Clinical trial; Endoscopic ultrasound (EUS); Fine needle biopsy (FNB); Solid pancreatic Lesions; Tissue acquisition techniques.