Survival prediction for patients with malignant biliary obstruction caused by pancreatic cancer undergoing biliary drainage: the COMBO-PaS model.

ABSTRACT

BACKGROUND: Patients with pancreatic cancer-caused biliary obstruction (PC-BO) have poor prognosis, but we lack of tools to predict survival for clinical decision-making. This study aims to establish a model for survival prediction among patients with PC-BO. METHODS: A total of 172 patients with PC-BO treated with percutaneous biliary drainage were randomly divided into a training group (n = 120) and a validation group (n = 52). The independent risk factors for overall survival were selected to develop a Cox model. The predictive performance of M stage, hepatic metastases, cancer antigen 199, and the Cox model was determined. Naples prognostic score (NPS), the prognostic nutritional index (PNI), and the controlling nutritional status (CONUT) for 1-month mortality risk were compared with the Cox model. RESULTS: The Cox model was developed based on total cholesterol, direct bilirubin, hepatic metastases, cancer antigen 199, stenosis type, and preprocedural infection (all P < 0.05), which named "COMBO-PaS." The COMBO-PaS model had the highest area under the curves (AUC) (0.801-0.933) comparing with other predictors (0.506-0.740) for 1-, 3-, and 6-month survival prediction. For 1-month mortality risk prediction, the COMBO-PaS model had the highest AUC of 0.829 comparing with NPS, PNI, and CONUT. CONCLUSION: The COMBO-PaS model was useful for survival prediction among patients with PC-BO.