AbstractThe prognostic role of the Age-Adjusted Charlson Comorbidity Index (ACCI) in hilar cholangiocarcinoma patients undergoing laparoscopic resection is unclear. To evaluate ACCI's effect on overall survival (OS) and recurrence-free survival (RFS), we gathered data from 136 patients who underwent laparoscopic resection for hilar cholangiocarcinoma at Zhengzhou University People’s Hospital between 1 June 2018 and 1 June 2022. ACCI scores were categorized into high ACCI (ACCI > 4.0) and low ACCI (ACCI ≤ 4.0) groups. We examined ACCI's association with OS and RFS using Cox regression analyses and developed an ACCI-based nomogram for survival prediction. Our analysis revealed that higher ACCI scores (ACCI > 4.0) (HR = 2.14, 95%CI: 1.37–3.34) were identified as an independent risk factor significantly affecting both OS and RFS in postoperative patients with hilar cholangiocarcinoma (p < 0.05). TNM stage III-IV (HR = 7.42, 95%CI: 3.11–17.68), not undergoing R0 resection (HR = 1.58, 95%CI: 1.01–2.46), hemorrhage quantity > 350 mL (HR = 1.92, 95%CI: 1.24–2.97), and not receiving chemotherapy (HR = 1.89, 95%CI: 1.21–2.95) were also independent risk factors for OS. The ACCI-based nomogram accurately predicted the 1-, 2-, and 3-year OS rates, with Area Under the Curve (AUC) values of 0.818, 0.844, and 0.924, respectively. Calibration curves confirmed the nomogram’s accuracy, and decision curve analysis highlighted its superior predictive performance. These findings suggest that a higher ACCI is associated with a worse prognosis in patients undergoing laparoscopic resection for hilar cholangiocarcinoma. The ACCI-based nomogram could aid clinicians in making accurate predictions about patient survival and facilitate individualized treatment planning.Keywords: Hilar cholangiocarcinomaage-adjusted Charlson comorbidity indexlaparoscopic resectionprognosisnomogram AcknowledgmentsThanks to all the researchers and patients who have made efforts in the research.Ethical approvalThis study was conducted in strict adherence to the ethical guidelines and principles of the Declaration of Helsinki and was approved by the Ethics Committee of Zhengzhou University People’s Hospital ((2023) Ethic Review No.(12)). This research is a retrospective study that only collected patient data from medical records. Informed consent from the participants was waived by the Ethics Committee of Zhengzhou University People’s Hospital ((2023) Ethic Review No.(12)).Disclosure statementNo potential conflict of interest was reported by the author(s).Data availability statementNot applicable.Additional informationFundingThis study was supported by the Science and Technology Tackling Program of Henan Province (212102310131).