Levels of pretreatment serum lipids predict responses to PD-1 inhibitor treatment in advanced intrahepatic cholangiocarcinoma

•All the serum lipids showed good discriminatory ability in terms of OS.•The higher the lipid levels, the better the prognosis.•Serum lipid levels were used as a prognostic nomogram in the prediction of anti-PD-1 therapy efficacy in patients with iCCA. It has been identified that serum lipids can be used as prognostic biomarkers in several types of cancer and are associated with patient survival. We aimed to clarify the prognostic value of the serum lipids and to establish a novel effective nomogram for overall survival (OS) in intrahepatic cholangiocarcinoma (iCCA) patients receiving anti-PD1 therapy. Pretreatment serum lipids were retrospectively analyzed for prognostic value, including apolipoprotein B (APOB), apolipoproteinA-1 (APOA1), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG), which were assessed for prediction accuracy using Kaplan–Meier survival curves and time-dependent receiver operating characteristic (ROC). Cox regression analysis with univariate and multivariate factors was used to identify prognostic factors predictive of OS, and prognostic nomograms were constructed. All the serum lipids showed good discriminatory ability in terms of OS (all P