Gallbladder Cancer: A Single-Institution 10-Year Experience-Analysis of Adenocarcinoma Subtypes and Tumors Arising from Intracholecystic Papillary Neoplasms.

ABSTRACT

BACKGROUND: Gallbladder cancer accounts for 1.2% of global cancer diagnoses. Literature on biliary-type adenocarcinoma (BTA), and specifically carcinoma arising from intracholecystic papillary-tubular neoplasms (ICPNs), is limited. This study describes a retrospective, single-institution experience with gallbladder cancer, focusing on histological subtypes and prognosis. METHODS: A retrospective review was performed of patients who underwent cholecystectomy for a malignant neoplasm of the gallbladder between 2007 and 2017. Demographic, clinicopathologic, and operative variables, as well as survival outcomes, were analyzed. RESULTS: From a total of 145 patients, BTAs were most common (93, 64%). Compared with non-BTAs, BTAs were diagnosed at a lower American Joint Committee on Cancer stage (p = 0.045) and demonstrated longer median recurrence-free survival (38 vs. 16 months, p = 0.014; median follow-up 36 months). Tumors arising from ICPNs (18, 12%) were more commonly associated with BTA (14 cases). Compared with BTAs not associated with ICPNs (29 patients), associated cases demonstrated lower pathologic stage (p = 0.006) and lower rates of liver and perineural invasion (0% vs. 49% and 14% vs. 48%, respectively; p < 0.05). Cumulative 5-year survival probability was higher for patients with gallbladder neoplasm of any subtype associated with ICPNs compared with those that were not associated with ICPNs (54% vs. 41%, p = 0.019; median follow-up 23 months). This difference was also significant when comparing BTAs associated with ICPNs and non-associated cases (63% vs. 52%, p = 0.005). CONCLUSIONS: This study demonstrated unique pathological and prognostic features of BTAs and of carcinomas arising from ICPNs. Histopathological variance may implicate prognosis and may be used to better guide clinical decision making in the treatment of these patients.