To explore the prognostic factors of patients with intrahepatic cholangiocarcinoma (ICC) after surgical resection and establish a nomogram for survival prediction.

A total of 160 patients with ICC who underwent surgical resection in the First Affiliated Hospital of Xi′an Jiaotong University from January 2010 to December 2018 were retrospectively analyzed. Among them, 89 patients were males and 71 were females, aged from 29 to 81 years with a age of (57.41±10.35) years. Observation indicators included: (1) The result of follow-up: postoperative survival. (2) The univariate analysis and multivariate analysis affecting postoperative patients′ prognosis. (3) The establishment and validation of nomogram model. The follow-up using outpatient and telephone was performed once every 3 months within 1 year postoperatively and once every 3-6 months after 1 year postoperatively up to August 1, 2019. The follow-up included liver function, CA19-9, upper abdominal ultrasound, CT or MRI. The overall postoperative survival time, end point of observation, was the date from the operation date to the follow-up date, or the date of death due to tumor recurrence and metastasis. The patients′ clinicopathological data was included in the prognostic factor analysis, the Kaplan-meier method and Log-rank test were conducted for the univariate analysis, the Cox proportional risk regression model was used for the multivariate analysis. The independent risk factors based on Cox regression model were screened to establish a nomogram for postoperative survival prediction. The patients were divided into the model group (n=112) for the establishment of survival nomogram and the validation group (n=48) for the assessment of predictive ability at a ratio of 7∶3, and the accuracy of nomogram in postoperative survival prediction was assessed by c-index. Measurement data with normal distribution were expressed with (Mean±SD). Measurement data with skewed distribution were described as M (range). Count data were expressed as cases and percentage.

During the follow-up period, all patients with ICC after surgical resection were followed up for a survival time of 20 months (2-111 months). 100 patients died of multiple organ failure caused by tumor recurrence and metastasis and 60 patients survived. The 1-, 3- and 5-year overall survival rates of patients were 63.3%, 30.0% and 19.6%, respectively. Univariate analysis showed that CA19-9, hepatolithiasis, number of tumor, range of liver resection, tumor differentiation, pathology type, tumor diameter, vascular invasion, TNM stage, lymphatic metastasis, satellite foci and surgical margin were the prognostic factors of ICC patients after surgical resection (HR=1.78, 1.97, 2.91, 1.89, 3.06, 2.86, 2.07, 1.94, 2.24, 1.95, 2.68, 2.00, 95%CI: 1.12-2.85, 1.22-3.16, 1.85-4.56, 1.26-2.85, 1.38-6.82, 1.31-6.25, 1.37-3.14, 1.07-3.51, 1.24-4.06, 1.26-3.01, 1.28-5.60, 1.11-3.59, P<0.05). Multivariate analysis showed that hepatolithiasis, number of tumor, range of liver resection, tumor differentiation (low differentiation) and pathology type were independent risk factors of ICC patients after surgical resection (HR=2.47, 2.37, 2.06, 5.52, 5.72, 95%CI: 1.39-4.38, 1.44-3.91, 1.25-3.40, 1.24-24.49, 2.31-14.17, P<0.05). The nomogram was established based on above five independent risk factors, the c-index value for postoperative survival of the model group and validation group were 0.71 (95%CI: 0.64-0.79) and 0.71(95%CI: 0.61-0.81), respectively.

A nomogram based on hepatolithiasis, number of tumor, range of liver resection, tumor differentiation and pathology type has better accuracy in postoperative survival prediction for patients with ICC.

Bile duct neoplasms; Prognosis; Nomograms; Intrahepatic cholangiocarcinoma; Survival prediction