Early radiotherapy versus late radiotherapy after incomplete transarterial chemoembolization in hepatocellular carcinoma.

Abstract

459 Background: To investigate the efficacy of early RT (ERT) in comparison to late RT (LRT) in HCC patients after incomplete TACE. Methods: Between January 2006 and December 2011, 99 BCLC B and C stage HCC patients were reviewed. We defined ERT as curative aimed additional RT after the first TACE, and LRT was defined as salvage aimed additional RT for recurrent or re-growing remnant tumors after repeated TACE. The median prescribed dose was 45 Gy (range, 21.6 Gy–60 Gy) given in daily dose of 1.8 Gy–3 Gy. Three-dimensional conformal RT or intensity modulated RT was used for all patients. The in-field tumor response rate (IFTR) was evaluated using the modified response evaluation criteria in solid tumors. Results: Fifty eight (58.6%) patients received ERT and 41 (41.4%) patients received LRT. All patients had BCLC B-C stage HCC and the characteristics between two groups were not different significantly. However, vessel invasion was observed more often in the LRT group (p=0.039). The median interval between last TACE and RT was 2weeks in the ERT group, and 4 weeks in the LRT group. The IFTR at one month and three months were significantly higher in the ERT group. The one-year in-field progression-free survival rates were 79.5% and 45.9% in the ERT and LRT groups, respectively (p=0.007).The one-year overall survival rates were 75.9% and 48.8% in the ERT and LRT groups, respectively (p = 0.01). In the multivariate analysis, vessel invasion and treatment group (ERT vs.LRT) were independent predictor of OS (p=0.039 and p=0.035). PVTT and treatment group (ERT vs.LRT) showed correlation with IFPFS in the multivariate analysis (p=0.002 and p=0.01). Conclusions: While this finding may reflect differences in biological characteristics between the two groups, ERT within 2weeks after incomplete TACE should be considered.