The rationale against a "mandatory" extended hepatectomy in perihilar cholangiocarcinoma: meta-analysis.

[INTRODUCTION] Traditional surgical teaching includes an extended hepatectomy for patients diagnosed with perihilar cholangiocarcinoma (pCCA). However, recent studies suggest it may not consistently lead to the best outcome.

[METHODS] A systematic review was conducted in PubMed, Embase, and Web of Science databases (inception - March 2025). Studies including at least 50 patients with pCCA who underwent liver and extrahepatic bile duct resection with caudate lobe were included. For each study, resections were reclassified as "Reference Surgery" (RS) or "Extended Surgery" (ES) according to the Kawaguchi-Gayet classification. Primary outcome was overall survival (OS). Secondary outcomes included: microscopic residual disease (R1), post-hepatectomy liver failure (PHLF), 90-day mortality rates. Hazard Ratios (HR), Odds Ratios (OR) with 95% Confidence Intervals (CI) represented outcome measures. Results after sensitivity analysis are reported.

[RESULTS] Overall, 4181 patients with resected pCCA from 17 retrospective studies were included. Proportion for Bismuth type was similar, except for type 3a (RS: 9.6%; ES: 41.6%). RS primarily comprised left hepatectomy (64.2%; n = 1090); ES mainly included right extended hepatectomy (35.7%; n = 1001). Overall, ES was negatively associated with OS (HR = 1.2; 95% CI = 1.07-1.34), did not improve R1 rate (OR = 0.91; 95% CI = 0.71-1.15), and was associated with a two-fold higher risk of PHLF and 90-day mortality.

[CONCLUSIONS] Accounting for confounding, this study shows no clear benefit of ES over RS for pCCA, suggesting non-inferiority of RS. Surgeons may consider a safer parenchymal sparing approach as long as radicality is not significantly compromised, especially for patients at higher risk of fatal PHLF.