The 7th/8th American Joint Committee on Cancer and the Modified Union for International Cancer Control Staging System for Hepatocellular Carcinoma

ABSTRACT

PURPOSE: Although many staging systems have been proposed for hepatocellular carcinoma (HCC), there is no globally accepted system due to the extreme heterogeneity of the disease. We aimed to compare the results of the 7th/8th American Joint Committee on Cancer (AJCC) and the modified Union for International Cancer Control (mUICC) staging systems in patients with HCC. MATERIALS AND METHODS: We collected data from 792 patients who underwent hepatic resection at our center. The Kaplan-Meier method was used to determine disease-free survival and overall survival. To evaluate homogeneity, ‘-2 log likelihood’ was calculated using Cox proportional hazards regression. To measure discriminatory ability, the linear trend chi method and the Cochran-Armitage test for trend were used. The ability to accurately predict survival was verified by cross-validation analysis. RESULTS: Kaplan-Meier curves for disease-free survival and overall survival showed mUICC to be superior to the 7th/8th AJCC. The homogeneity test indicated that mUICC was the best for both disease-free survival and overall survival. In the discriminatory ability test, the chi-square value of mUICC was the best for disease-free survival, while the 7th AJCC had the best value for overall survival. In the cross-validation analysis, all three staging systems had significant predictive power. CONCLUSION: mUICC seemed to be superior to the 7th/8th AJCC after analyzing the data of our surgical patients, although the geographic heterogeneity of HCC might result in differences between the staging systems. We believe that, while the three staging systems allow for the clear stratification of patients into prognostic groups, mUICC may be more appropriate in HCC.