A comparison of outcomes in patients with intracholecystic papillary neoplasms or conventional adenocarcinomas of the gallbladder

Background: Intracholecystic papillary neoplasm (ICPN) of the gallbladder (GB) is an exophytic intraepithelial neoplasm. This study aimed to investigate clinicopathologic findings, prognosis and recurrence patterns of patients with ICPN as compared to those patients with conventional adenocarcinoma of the gallbladder (GBC). Methods: Patients who underwent surgical resection for suspected GB cancer between 2000 and 2018 were included. ICPN was defined as an exophytic papillary mass within the GB lumen with a size >1.0 cm. Results: Of 607 patients, 241 patients (40%) were pathologically diagnosed with ICPN. Of the 241 patients with ICPNs, 110 (46%) were T1 or less. Following T stage-matched analysis, the rate of lymph node metastases were comparable (50 [52%] vs. 37 [49%], P = 0.581). The five-year survival rate was higher in ICPN, but after T stage-matching, they were comparable (69.1 vs. 63.2%, P = 0.171). Overall recurrence rates were also comparable, with the exception of lower peritoneal seeding in patients with ICPN. Conclusion: Patients with ICPN who underwent resection were more likely to have an earlier T stage. There was no significant difference in prognosis and recurrence between ICPN and conventional GBC after stage matching. Therefore, the treatment strategy for ICPN should follow the same protocols used for conventional GBC.