Cholecystectomy is associated with higher risk of recurrence after microwave ablation of hepatocellular carcinoma: a propensity score matching analysis

Objective: To explore the association between cholecystectomy and the prognostic outcomes of patients with hepatocellular carcinoma (HCC) who underwent microwave ablation (MWA). Methods: Patients with HCC (n = 921) who underwent MWA were included and divided into cholecystectomy (n = 114) and non-cholecystectomy groups (n = 807). After propensity score matching (PSM) at a 1:2 ratio, overall survival (OS) and disease-free survival (DFS) rates were analyzed to compare prognostic outcomes between the cholecystectomy (n = 114) and non-cholecystectomy groups (n = 228). Univariate and multivariate Cox analyses were performed to assess potential risk factors for OS and DFS. Major complications were also compared between the groups. Results: After matching, no significant differences between groups were observed in baseline characteristics. The 1-, 3-, and 5-year OS rates were 96.5%, 82.1%, and 67.1% in the cholecystectomy group, and 97.4%, 85.2%, and 74.4% in the non-cholecystectomy group (P = 0.396); the 1-, 3-, and 5-year DFS rates were 58.4%, 34.5%, and 26.6% in the cholecystectomy group, and 73.6%, 44.7%, and 32.2% in the non-cholecystectomy group (P = 0.026), respectively. The intrahepatic distant recurrence rate in the cholecystectomy group was significantly higher than that in the non-cholecystectomy group (P = 0.026), and the local tumor recurrence and extrahepatic recurrence rates did not significantly differ between the groups (P = 0.609 and P = 0.879). Multivariate analysis revealed that cholecystectomy (HR = 1.364, 95% CI 1.023-1.819, P = 0.035), number of tumors (2 vs. 1: HR = 2.744, 95% CI 1.925-3.912, P < 0.001; 3 vs. 1: HR = 3.411, 95% CI 2.021-5.759, P < 0.001), and gamma-GT levels (HR = 1.003, 95% CI 1.000-1.006, P < 0.024) were independent risk factors for DFS. The best gamma-GT level cut-off value for predicting median DFS was 39.6 U/L (area under the curve = 0.600, P < 0.05). A positive correlation was observed between cholecystectomy and gamma-GT level (r = 0.108, 95% CI -0.001-0.214, P = 0.047). Subgroup analysis showed that the DFS rates were significantly higher in the non-cholecystectomy group than the cholecystectomy group when gamma-GT >= 39.6 U/L (P = 0.044). The 5-, 10-, 15-, 20-, and 25-year recurrence rates from the time of cholecystectomy were 2.63%, 21.93%, 42.11%, 58.77%, and 65.79%, respectively. A significant positive correlation was observed between cholecystectomy and the time from cholecystectomy to recurrence (r = 0.205, 95% CI 0.016-0.379, P = 0.029). There were no significant differences in complications between groups (P = 0.685). Conclusions: Patients with HCC who underwent cholecystectomy were more likely to develop intrahepatic distant recurrence after MWA, an outcome probably associated with increased gamma-GT levels. Moreover, the recurrence rates increased with time.