To explore the factors affecting the prognosis and survival of patients with unresectable biliary tract cancer caalignant biliary obstruction after interventional therapy, and to construct an individualized nomogram to predict the overall survival time (overall survival, OS).

From June 2015 to July 2021, a total of 261 patients with obstructive jaundice caused by unresectable biliary tract cancer treated with interventional decompression in our center were retrospectively analyzed. The patients were divided into two groups: a training group (n = 188) and a validation group (n = 73). The univariate and multivariate Cox proportional hazard regression analyses were used to determine the independent factors related to OS, and an individual nomogram was constructed to visualize the new model and predict 3-month, 6-month, and 1-year survival. The area under the curves (AUC) and the calibration curves were drawn to evaluate predictive performance in total patients . The risk stratification ability of each categorical predictors was evaluated by Kaplan-Meier curves.

For the enrolled patients, the median OS was 244 days (IQR: 213, 275) in the training group and 236 days (IQR: 186, 285) in the validation group. The univariate and multivariate regression analyses showed that the independent factors were total bilirubin, total cholesterol, hemoglobin, serum sodium, carbohydrate antigen-9 and subtypes of tumor. A nomogram was successfully established to predict 3-months, 6-month and 1-year survival probability. The AUCs showed that the new model had good discrimination for 3-month, 6-month and 1-year OS prediction in the training group (0.817, 0.825 and 0.796, respectively) and the calibration group (0.921, 0.880 and 0.904, respectively).

The new model could effectively predict 3 months, 6 months and 1 year OS for patients with unresectable biliary tract cancer caused obstructive jaundice undergoing interventional decompression, which may help for clinical decision making.