Intrahepatic or peripheral cholangiocarcinoma (ICC) accounts for approximately 10% of primary liver malignancies and is second only to hepatocellular carcinoma. Due to the absence of early symptomatology, tumours are often observed in the late stages, thus conferring a poor prognosis. Although the most effective treatment for ICC is complete hepatic tumour excision, the prognosis after surgery remains disappointing due to early and frequent systemic spread of disease. Variables correlated with poor survival in ICC patients have been identified; however, no predictive mathematical survival model that accounts for these variables has been proposed. Accordingly, this retrospective study assessed the risk factors for survival in ICC patients who underwent hepatectomy, and attempted to construct a mathematical model for predicting survival.
Currently, the most effective treatment for intrahepatic cholangiocarcinoma (ICC) is complete hepatic tumour excision.
To identify the clinical parameters associated with survival duration for ICC patients following hepatectomy, and to construct a mathematical model for predicting survival duration.
Demographic data and clinical variables for 102 patients diagnosed with ICC, who underwent exploratory laparotomy at a single centre from July 1998 to December 2000 and were followed for an average of 24 months, were collected in 2011. Patients were randomly assigned into training (n=76) and validation (n=26) groups. Univariate and multivariate analyses were performed to identify factors associated with posthepatectomy survival duration.
Univariate analysis revealed that more than three lymph node metastases, a serum carbohydrate antigen 19-9 level >37 U/mL, stage IVa tumours, and intra- or perihepatic metastases were significantly associated with decreased survival duration. Curative resection was significantly associated with increased survival duration. A mathematical model incorporating parameters of age, sex, metastatic lymph node number, curative surgery, carbohydrate antigen 19-9 concentration, alpha-fetoprotein concentration, hepatitis B, TNM stage and tumour differentiation was constructed for predicting survival duration. For a survival duration of less than one year, the model exhibited 93.8% sensitivity, 92.3% total accuracy and a positive predictive value of 93.8%; for a survival duration of one to three years, the corresponding values were 80.0%, 69.2% and 57.1%, repsectively.
The mathematical model presented in the current report should prove to be useful in the clinical setting for predicting the extent to which curative resection affects the survival of ICC patients, and for selecting optimal postoperative treatment strategies.