Endoscopic ultrasound-guided biopsy of healthy pig pancreas - Towards the histological diagnosis of chronic pancreatitis

Abstract

Background: diagnosis of early chronic pancreatitis (CP) is a challenge due to the lack of accurate methods. The ability of endoscopic ultrasound (EUS) guided biopsy to obtain pancreatic core tissue samples in patients with minimal changes of CP and its potential use for the histological diagnosis of early CP are unknown. The aim of the study was to evaluate the ability of different EUS-guided biopsy core needles to obtain histological samples of healthy pig pancreas.

Methods: an observational, feasibility, comparative, single blind study was performed in two pigs, of two months old, weighing 22 kg. EUS-guided biopsy was performed from the body of the pancreas. Core needles of 19-gauge, 20-gauge, 22-gauge and 25-gauge were used. Two passes with ten to-and-fro movements were performed with each needle. Samples were evaluated by blinded expert pathologists. Primary end point was the ability to obtain core tissue samples. Secondary end point included fragmentation, core size, amount of blood and sample quality for histological assessment.

Results: a core tissue sample was obtained with 19-gauge, 20-gauge and 22-gauge core needles. The mean size of the tissue core was 2.38 ± 1.06 mm (range 1-4 mm). Tissue samples were considered as adequate for histological evaluation with 19-gauge and 22-gauge Franseen and fork-tip and 20-gauge reverse bevel needles. No complications related to the procedure were reported.

Conclusions: obtaining a core tissue sample of healthy pancreas by EUS-guided biopsy is feasible. Whether EUS-guided biopsy using these needles is accurate and safe for the histological diagnosis of early CP deserves further investigations.