Preoperative prognostic nutritional index predicts postoperative infectious complications and oncological outcomes after hepatectomy in intrahepatic cholangiocarcinoma

Background In the surgical treatment of intrahepatic cholangiocarcinoma (ICC), postoperative complications may be predictive of long-term survival. This study aimed to identify an immune-nutritional index (INI) that can be used for preoperative prediction of complications. Patients and methods Multi-institutional data from 316 patients with ICC who had undergone surgical resection were retrospectively analysed, with a focus on various preoperative INIs. Results Severe complications (Clavien-Dindo grade III–V) were identified in 66 patients (20.8%), including Grade V complications in 7 patients (2.2%). Comparison of areas under the receiver operating characteristic curve (AUCs) among various INIs identified the prognostic nutritional index (PNI) as offering the highest predictive value for severe complications (AUC = 0.609, cut-off = 50, P = 0.008). Multivariate analysis revealed PNI < 50 (odds ratio [OR] = 2.22, P = 0.013), hilar lesion (OR = 2.46, P = 0.026), and long operation time (OR = 1.003, P = 0.029) as independent risk factors for severe complications. In comparing a high-PNI group (PNI ≥ 50, n = 142) and a low-PNI group (PNI < 50, n = 174), the low-PNI group showed higher rates of both major complications (27% vs. 13.4%; P = 0.003) and infectious complications (14.9% vs. 3.5%; P = 0.0021). Furthermore, median survival time and 1- and 5-year overall survival rates were 34.2 months and 77.4 and 33.8% in the low-PNI group, respectively, and 52.4 months and 89.3 and 47.5% in the high-PNI group, respectively ( P = 0.0017). Conclusion Preoperative PNI appears useful as an INI correlating with postoperative severe complications and as a prognostic indicator for ICC.