Per Protocol Analysis and Long‐Term Outcomes of Laparoscopic Radical Resection for Gallbladder Cancer Compared With Open Method

BACKGROUND: Although laparoscopic radical resection for gallbladder (GB) cancer has been attempted, only a limited number of studies have evaluated its outcomes using a per-protocol analytical approach. METHODS: Between January 2010 and December 2019, 213 patients underwent surgery for gallbladder (GB) cancer at three institutions, of whom 203 consecutive patients with T2 or T3 disease were retrospectively analyzed. Protocol-adherent radical resection (per-protocol) was defined as wedge liver resection or IVb/V bisegmentectomy with the procurement of at least four lymph nodes. Propensity score matching was performed to compare the laparoscopic and open approaches. RESULTS: Protocol-adherent radical resection was achieved in 14 of 76 patients (18.4%) in the laparoscopic group and in 76 of 127 patients (59.8%) in the open surgery group. The primary unmet criterion for radical resection was an insufficient lymph node yield (60/76, 78.9%) in the laparoscopic group. After 1:1 propensity score matching (54 pairs), the 5-year overall survival (OS) rate did not differ between the laparoscopic and open approaches (46.1% vs. 49.9%; hazard ratio 0.90, 95% confidence interval 0.55-1.47; p = 0.668), whereas the disparity in oncological adequacy persisted (protocol-adherent radical resection 20.4% vs. 70.4%). Among patients who achieved protocol-adherent radical resection (N = 90), the exploratory comparison of 5-year OS between the laparoscopic (N = 14) and open (N = 76) groups showed no significant difference (61.5% vs. 53.3%; p = 0.288). Multivariate analysis in patients with protocol-adherent radical resection identified N stage and elevated CA 19-9 levels as independent prognostic factors for OS. CONCLUSIONS: Regardless of whether a laparoscopic or open approach is used, radical surgery-including appropriate hepatic resection with the retrieval of at least four lymph nodes-is essential for improving long-term prognosis in patients with GB cancer. N stage and elevated CA 19-9 levels were independently associated with overall survival.