Characteristics and Management of Incidental Gallbladder Cancer: Impact and Limitation of Laparoscopic Whole Layer Cholecystectomy

Abstract

Introduction: Incidental Gallbladder Cancer (IGBC) is a status of gallbladder cancer (GBC) that has not been diagnosed as cancer preoperatively. Efficacy of laparoscopic whole layer cholecystectomy (LWC) for early stage GBC is reported. However, there is no report about effect of LWC on IGBC. We are reporting the risk factors of recurrence of IGBC and strategy for IGBC from experience of a high-volume center in Japan. Methods: We retrospectively investigated on 3166 patients who were undergone cholecystectomy with preoperative diagnosis of benign disease in our hospital from 2009 to 2018. Results: Fifty-one patients (1.61%) were diagnosed as IGBC. Preoperative diagnoses were acute cholecystitis (16/1106, 1.45%), chronic cholecystitis (4/117, 3.42%), gallbladder polyp (19/151, 10.60%), adenomyomatosis (3/107, 2.80%) and gallbladder stone (9/1580, 0.57%). Post-operative recurrence was observed on 19 cases. Risk factors for recurrence on univariate analysis were bile spillage (p=0.001), advanced stage (p=0.002), positive surgical margin (p=0.005) and non-LWC (p=0.047). On multivariate analysis, bile spillage was only significant factor of recurrence (p=0.024, OR=11.43). No bile spillage was occurred on any of 10 patients performed LWC. Six patients of T1 were undergone LWC and no patients were relapsed. Risk factor of recurrence among advanced stage patients were non-additional resection (p=0.010) and bile spillage (p=0.036), but LWC was not significant (p=0.228). Conclusion: Bile spillage was significant risk factor of recurrence on IGBC. LWC is an efficacious procedure on T1 IGBC, and LWC is recommended on IGBC suspected disease such as gallbladder polyp. For advanced stage, additional resection should be performed.