# Comparative analysis of differences for pathological upgrade and incomplete resection in endoscopic snare papillectomy for ampullary adenomas: A single-institution retrospective study

## TL;DR

This study compares factors linked to changes in diagnosis and incomplete removal after surgery for ampullary adenomas using endoscopic techniques.

## Contribution

The study identifies clinical and endoscopic features associated with pathological upgrades and incomplete resection after endoscopic snare papillectomy.

## Key findings

- Pathological upgrades occurred in 17 out of 40 patients after endoscopic snare papillectomy.
- Clinical and endoscopic features like ALT, ALP, and EUS findings differed between groups with and without pathological upgrades.
- Incomplete resection was associated with specific lab values and bile duct characteristics identified via EUS.

## Abstract

Inconsistent pathological diagnoses between pre- and post-endoscopic snare papillectomy (ESP) biopsies were frequently observed. We aimed to compare the differences in pathological upgrade and incomplete resection between endoscopic snare papillectomy for ampullary adenomas.

The included patients were those referred to Sir Run Run Shaw Hospital and underwent ESP for an ampullary adenoma between 2012 and 2022. The endoscopic and clinicopathological features of ampullary adenomas were obtained using white light endoscopy, narrow-band imaging endoscopy, and endoscopic ultrasound (EUS). Adverse events, histological diagnosis, and follow-up data were also collected.

Overall, 40 patients underwent ESP of ampullary adenomas and were included in the study. Seventeen patients had inconsistent pre- and post-ESP pathological diagnoses, as they were upgraded from either low-grade dysplasia (LGD) to high-grade dysplasia (HGD) or from HGD to adenocarcinoma. Various characteristics varied between the pathological upgrade and non-upgrade groups, such as alanine transaminase (ALT), alkaline phosphatase levels (ALP), erosion and redness of papilla, a hybrid histological type, procedure time and extended lower bile duct width identified through EUS. Differences were observed between the complete and incomplete resection groups in terms of ALT, Gamma-glutamyl transferase (GGT) levels, tumor extension into the bile duct, and width of lower bile duct extension as determined by EUS.

Pathological upgrading were relatively common after ESP for ampullary adenomas. Preoperative identification of specific clinical and endoscopic features can enhance diagnostic accuracy and inform treatment strategies.