# Endoscopic Ultrasound‐guided Fine‐Needle Biopsy With End‐Cutting Needles in Autoimmune Pancreatitis: A Systematic Review and Meta‐Analysis

## TL;DR

This study finds that end-cutting needles in endoscopic ultrasound-guided biopsies are more effective for diagnosing autoimmune pancreatitis compared to other needle types.

## Contribution

The study provides a meta-analysis comparing diagnostic performance of different needle types in autoimmune pancreatitis biopsies.

## Key findings

- End-cutting needles showed 80% diagnostic accuracy compared to 49% with reverse bevel needles.
- Franseen and Fork-tip needles had the highest diagnostic accuracy rates.
- EUS-FNB provided a definitive diagnosis in 77% of cases with low adverse event rates.

## Abstract

There is limited evidence on the diagnostic yield of endoscopic ultrasound (EUS)‐guided tissue acquisition (TA) using fine‐needle biopsy (FNB) in autoimmune pancreatitis (AIP), particularly considering the newer end‐cutting needles. The aim of this meta‐analysis was to provide a pooled estimate of the diagnostic performance of EUS‐TA using FNB in AIP patients according to the needle type used.

A computerized bibliographic search was performed through April 2024. Pooled effects were calculated using a random‐effects model. The primary endpoint was diagnostic accuracy. Secondary outcomes were sample adequacy, rates of adequate material for levels 1 and 2 of histological diagnosis, definitive diagnosis reached with histology in addition to imaging/laboratory tests, and safety.

Twelve studies (three prospective series and one randomized trial) with 496 patients were included. Overall diagnostic accuracy rate was 75% (66%–83%), with a superiority of end‐cutting needles over reverse bevel needles (80%, 70%–90% versus 49%, 21%–67%; p < 0.001). Franseen (81%, 68%–93%) and Fork‐tip needles (86%, 74%–98%) showed the highest accuracy. Sample adequacy rate was 92% (87%–98%), and EUS‐TA using FNB provided level 1 of histological diagnosis in 47% of cases (38%–57%) and level 2 in 23% (16%–30%). EUS‐TA using FNB provided a definitive diagnosis in 77% (63%–91%) of cases. Pooled rate of adverse event was 2% (1%–3%), mainly mild pancreatitis.

End‐cutting needles showed high diagnostic yield in patients with AIP, with a low rate of adverse events, and should be preferred over reverse bevel needles.