Background and study aims  Endoscopic papillectomy (EP) is a minimally invasive treatment for ampullary neoplasms and is recognized as an alternative treatment to surgical resection; however, there are few reports on a suitable pancreatic stent (PS) after EP for preventing pancreatitis. The aim of this study was to evaluate the efficacy of a long PS after EP. Patients and methods  In this retrospective single-center study, 39 patients with pathologically proven ampullary neoplasms who underwent EP between March 2012 and August 2018 were enrolled. The study participants were divided into two subgroups according to the PS length: those with a PS shorter than 5 cm (short PS group, n = 17) and those with a PS of 7 cm (long PS group, n = 22). The incidence of adverse events and risk factors for pancreatitis were evaluated. Results  The diameter of all PSs was 5 Fr. Post-EP pancreatitis occurred in nine patients (23.1 %), with two cases of severe pancreatitis (5.1 %). Pancreatitis occurred more frequently in the short PS group (7/17, 41.2 %) than in the long PS group (2/22, 9.1 %) ( P  = 0.026). There were no significant differences between the two groups in terms of other adverse events. Univariate and multivariate analyses showed that a long PS was the only factor associated with a decreased incidence of post-EP pancreatitis ( P  = 0.042; odds ratio, 0.16; 95 % confidence interval, 0.027-0.94). Conclusion  A long (7 cm) PS significantly decreased incidence of pancreatitis after EP. Prospective randomized studies with a larger number of patients and wider range of PS lengths are required.

Hepatic cysts are the most frequent, innocuous, space-occupying lesions of the liver. The majority of solitary liver cysts are nonsymptomatic. When liver cysts reach a large size, there are some complications, including infection, rupture, spontaneous hemorrhage, obstructive jaundice, and neoplastic degeneration. Percutaneous aspiration, fenestration, hepatic resection, and liver transplantation have been proposed for symptomatic patients.

In this case report, we describe a 41-year-old woman who presented with persistent liver dysfunction, indolent xanthochromia, and skin itching for 3 months. After a series of tests, she has a 5.0 × 5.3 cm hepatic cyst with many separations in the left medial liver lobe. The obstructive jaundice was caused by a large pedunculated lump protruding into the common bile duct from the left hepatic duct. She was treated with laparotomy and this lump was completely removed from the root by choledochoscopic needle-knife electrotomy with a good clinical response. Postoperative pathology of the lump suggested a hepatic cyst wall without heterocysts or tumor cells.

Hepatic cyst wall protruding into the common bile duct can form capsular lump and result in indolent jaundice. Choledochoscopic high-frequency needle-knife electrotomy could be considered as a simple, safe and effective complementary approach for benign mass on the bile duct wall.