Survival Predictability Between the American Joint Committee on Cancer 8th Edition Staging System and the Barcelona Clinic Liver Cancer Classification in Patients with Hepatocellular Carcinoma

Abstract

This study compared the prognostic significance of staging between the American Joint Committee on Cancer 8th edition Tumor, Node, Metastasis (TNM) staging system and the Barcelona Clinic Liver Cancer (BCLC) classification in patients with hepatocellular carcinoma (HCC). The study population comprised patients with liver cancer registered in the Taiwan Cancer Database from 2007 to 2013 and was followed up until December 31, 2016. The study included patients with HCC, with known staging in both TNM and BCLC systems, and with follow-up >1 month. Primary endpoint was overall survival. Univariate and multivariate Cox proportional hazards model were constructed to investigate the significance of staging by two systems. Goodness-of-fit of model was evaluated via Akaike's information criterion (AIC), the lower the better. Among 73,136 patients with newly diagnosed liver cancer, a total of 37,062 patients with HCC (25.6% underwent surgery) were eligible. The mean age and overall survival of this cohort were 63.9 years and 27.2%, respectively. Overall survivals for stages I, II, III, and IV (the TNM system) were 54.5%, 34.9%, 10.3%, and 6.4%, respectively. Overall survivals for stages A, B, C, and D (the BCLC classification) were 54.5%, 29.2%, 9.8%, and 4.0%, respectively. The median follow-up time was 59.4 months. Multivariate Cox proportional hazards model revealed that both systems predicted overall survival, cancer-specific survival, disease-free survival, and local recurrence-free rate well. Values of ΔAIC of the BCLC classification and the TNM system were lower for the surgery group and nonsurgery group, respectively. The TNM system (8th edition) predicted long-term outcome better than the BCLC classification in patients with HCC. But in patients treated initially with surgery, the BCLC classification outperformed the 8th edition of the TNM system. IMPLICATIONS FOR PRACTICE: This work demonstrates that the Tumor, Node, Metastasis (TNM) system (8th edition) and the Barcelona Clinic Liver Cancer (BCLC) classification both predict long-term outcome significantly in patients with hepatocellular carcinoma but that the TNM system (8th edition) predicts long-term outcome better than the BCLC classification. For patients treated initially with surgery, BCLC classification outperforms in 8th edition TNM system in predicting long-term outcome.

Keywords: Barcelona Clinic Liver Cancer classification; Hepatocellular carcinoma; Overall survival; TNM staging system.