"Wet Heparin" and "Wet Saline" EUS-Guided Liver Biopsy Techniques Both Provide High Rates of Specimen Adequacy for Benign Parenchymal Liver Disease.

Background: Endoscopic ultrasound-guided liver biopsy (EUS-LB) has emerged as a viable mean to obtain core tissue, but the optimal tools and techniques are still an area of active investigation.

Aims: (1) To compare tissue adequacy using "wet saline" (WS) vs. "wet heparin" (WH) technique (2) To compare post-procedure pain between EUS-LB and percutaneous liver biopsy (PLB).

Methods: Retrospective review of consecutive patients who underwent EUS-LB and PLB for benign parenchymal liver disease between May 2017 to October 2019 at a single tertiary veterans affairs medical center.

Results: About 257 biopsies from 217 patients were included. Among the 102 EUS-LB specimens, 53 were obtained using WS technique and 49 were obtained using WH technique. Specimen adequacy was similar in both groups. Median Aggregate Specimen Length (ASL) and length of longest piece did not differ significantly between WS and WH groups. Clots were present more frequently in the WS group. Among patients who underwent EUS-LB of both right and left liver lobes, an adequate biopsy was obtained in 85% of patients in the WS group and 96% of patients in the WH group. The percentage of patients experiencing immediate post-procedure pain was higher with PLB compared to EUS-LB, but these results were not statistically significant.

Conclusions: Both WS and WH EUS-LB techniques can offer high rates of specimen adequacy with low rates of pain and other post-procedure complications.