Impact of sarcopenia on short- and long-term outcomes after resection of perihilar cholangiocarcinoma: a two-center study

Sarcopenia is associated with poor postoperative outcomes in patients with malignant tumors; however, its impact on perihilar cholangiocarcinoma (pCCA) patients remains unclear. This study aimed to evaluate the predictive value of sarcopenia for postoperative outcomes in patients undergoing resection for pCCA. A total of 271 patients with perihilar cholangiocarcinoma (pCCA) who underwent surgical intervention between 2016 and 2021 were retrospectively recruited from two institutions. The patients were divided into training and validation cohorts at a 7:3 ratio. Sarcopenia was defined via cutoff values for the skeletal muscle index (SMI) of 52.2 cm²/m² for males and 39.2 cm²/m² for females, which were determined through optimal stratification. Logistic regression and Cox proportional hazards regression were employed to identify significant risk factors associated with postoperative outcomes. Additionally, a novel nomogram based on sarcopenia was developed and subsequently validated via receiver operating characteristic (ROC) curves, calibration curves, and clinical decision curve analysis (DCA). Of the 271 patients studied, 144 (53.1%) were diagnosed with sarcopenia. Patients with sarcopenia presented significantly higher rates of total complications, major complications, and 90-day readmissions, as well as poorer overall survival (OS), than did those without sarcopenia. multivariable Cox regression analysis revealed several independent risk factors for OS, including body mass index (BMI) ( p = 0.026), high performance status (PS) score ( p < 0.001), R1 surgical margin ( p < 0.001), T stage IV ( p < 0.001), COUNT score ≥ 5 ( p = 0.005), and the presence of sarcopenia ( p < 0.001). A novel nomogram incorporating these six factors was developed to predict OS at 12, 24, and 36 months. The model exhibited robust predictive performance, with a mean area under the curve (AUC) greater than 0.8. The calibration curve closely matched the ideal curve, and decision curve analysis (DCA) further validated the strong predictive ability and substantial positive net benefit of the nomogram. Sarcopenia is a significant adverse factor for both postoperative complications and long-term survival in patients with pCCA following surgical resection.