The gold standard endpoint to evaluate the effect of treatment for hepatocellular carcinoma (HCC) is overall survival (OS), but it requires a longer follow-up period to observe. This study aimed to identify whether disease-free survival (DFS) could be used as a surrogate endpoint for OS to assess the efficacy of adjuvant therapies after curative treatment (surgical resection and ablation) for HCC patients. A systematic review was conducted to identify trials about curative treatment combined with or without adjuvant therapies (interferon, IFN; or transarterial chemoembolization, TACE) for HCC. Total of 2211 patients' data from 17 trials were analyzed. At the individual study level, DFS was strongly correlated to OS (rho = 0.988 and 0.930, 95% CI: 0.965-0.996 and 0.806-0.976 for the studies comparing Radiofrequency ablation (RFA) + TACE to RFA alone; and for the studies comparing curative treatment + IFN to curative treatment alone, respectively). At the trial level, the effects of treatment on DFS and OS were also strongly correlated to each other (R = 0.815 and 0.854, 95% CI: 0.536-0.934 and 0.621-0.948, respectively). In conclusion, DFS could be used as a potential surrogate endpoint for OS to assess the effect of adjuvant therapies after curative treatment for HCC.
Huan, H. B., Wu, L. L., Lau, W. Y., Wen, X. D., Zhang, L., Yang, D. P., … Xia, F. (2017). Surrogate endpoint for overall survival in assessment of adjuvant therapies after curative treatment for hepatocellular carcinoma: A re-analysis of meta-analyses of individual patients’ data. Oncotarget, 8(52), 90291–90300. https://doi.org/10.18632/oncotarget.18853