Construction of the Chinese University Prognostic Index for hepatocellular carcinoma and comparison with the TNM staging system, the Okuda staging system, and the Cancer of the Liver Italian Program staging system: a study based on 926 patients

Abstract

Background: The current TNM staging system for patients with hepatocellular carcinoma (HCC) does not include liver function parameters and does not provide a precise prognosis for patients in different risk groups. The objectives of this study were to construct a new prognostic index for patients with hepatocellular carcinoma, the Chinese University Prognostic Index (CUPI), and to compare it with existing staging systems in terms of their ability to classify patients into different risk group.

Methods: From 1996 to 1998, 926 ethnic Chinese patients who were diagnosed with HCC (mainly hepatitis B-associated) at a single institution were recruited prospectively into this study. A multivariate analysis on 19 patient characteristics was performed using a Cox regression model to identify independent prognostic factors. Weights were derived from the regression coefficients of various factors to construct the CUPI. Patients were classified according to different staging systems. Survival curves were plotted with the Kaplan-Meier method and were compared by using a log-rank test.

Results: Both the TNM staging system and the Okuda staging system had prognostic significance, but the significance was lower for the Cancer of the Liver Italian Program (CLIP) prognostic score among the patients in the study population. The CUPI was constructed by adding the following factors into the TNM staging system: total bilirubin, ascites, alkaline phosphatase, alpha fetoprotein, and asymptomatic disease on presentation. The new CUPI characterized three risk groups with highly significant differences in survival during the whole period of follow-up (P < 0.00001) and was more discriminant than the other systems.

Conclusions: In the study population of patients with mainly hepatitis B-associated HCC, the CUPI was more discriminant than the TNM staging system, the Okuda staging systems, or the CLIP prognostic score in classifying patients into different risk groups and was better at predicting survival. The CUPI needs to be validated by different cohorts of patients before it can be recommended for general use.