Anatomic versus non-anatomic resection for early-stage intrahepatic cholangiocarcinoma: a propensity score matching and stabilized inverse probability of treatment weighting analysis

Background Radical resection is still the most cost-effectiveness curative strategy for intrahepatic cholangiocarcinoma (ICC), but it remains controversial on the survival benefit of anatomic resection (AR). In this study, we sought to compare the oncologic outcomes between AR versus non-AR (NAR) as the primary treatment for early-stage ICC patients.Methods Data of ICC patients who underwent hepatectomy and staged at AJCC I were retrospectively collected from 12 hepatobiliary centers in China between Dec 2012 and Dec 2015. Propensity score matching (PSM) and stabilized inverse probability of treatment weighting (IPTW) analysis were performed to minimize the effect of potential confounders, and the perioperative and long-term outcomes between AR and NAR groups were compared.Results Two hundred seventy-eight ICC patients staged at AJCC I were eligible for this study, including 126 patients receiving AR and 152 patients receiving NAR. Compared to the NAR group, the AR group experienced more intraoperative blood loss before and after PSM or stabilized IPTW (all P > 0.05); AR group also experienced more intraoperative transfusion after stabilized IPTW (P > 0.05). In terms of disease-free survival (DFS) and overall survival (OS), no significant differences were observed between the two groups before and after PSM or stabilized IPTW (all P > 0.05). Multivariable Cox regression analyses found that AR was not an independent prognostic factor for either DFS or OS (all P > 0.05). Further analysis also showed that the survival benefit of AR was not found in any subgroup stratified by Child-Pugh grade (A or B), cirrhosis (presence or absence), tumor diameter (<= 5 cm or > 5 cm) and pathological type (mass-forming or non-mass-forming) with all P > 0.05.Conclusion Surgical approach does not influence the prognosis of patients with stage I primary ICC, and NAR might be acceptable and oncological safety.