Long-Term Oncologic Outcomes for T2 Gallbladder Cancer According to the Type of Surgery Performed and the Optimal Timing for Sequential Extended Cholecystectomy

Background: Sequential extended cholecystectomy (SEC) is currently recommended for T2 and higher gallbladder cancer (GBC) diagnosed after simple cholecystectomy (SC), but the value and timing of re-resection has not been fully studied. We evaluated the long-term oncologic outcomes of T2 GBC according to the type of surgery performed and investigated the optimal timing for SEC. Methods: Patients diagnosed with T2 GBC who underwent SC, extended cholecystectomy (EC), or SEC between 2002 and 2017 were retrospectively reviewed. Those who underwent other surgical procedures or those with incomplete medical records were excluded. Overall survival (OS) and disease-free survival (DFS) according to the types of surgeries and prognostic factors for OS and DFS were analyzed. Survival analysis was done between groups that were divided according to the optimal cutoff time interval between SC and SEC based on DFS data. Results: Of the 226 T2 GBC patients, 53, 173, and 44 underwent SC, EC, and SEC, respectively. The 5-year OS rate was 50.1%, 73.2%, and 78.7%, and the DFS rate was 46.8%, 66.3%, and 65.2% in the SC, EC, and SEC groups, respectively. EC (p = 0.001 and p = 0.001) and SEC (p = 0.007 and p = 0.065) groups had better 5-year OS and DFS rates than the SC group. Preoperative CA 19–9 level > 37 U/mL (HR 1.56; 95% CI 1.87–2.79; p < 0.001) and N1 stage (HR 2.88; 95% CI 1.76–4.71; p < 0.001) were associated with poorer prognosis. The optimal cutoff interval between SC and SEC was 28 days. Patients who underwent SEC ≤ 28 days after the initial cholecystectomy had better 5-year DFS rates than patients who underwent SEC after > 28 days (75.0% vs. 52.8%, p = 0.023). Conclusions: SEC is recommended for T2 GBC diagnosed after SC, because SEC provides better survival outcomes than SC alone. A time interval of less than 28 days to SEC is associated with an improved DFS.