Stereotactic ablative radiotherapy for unresectable hepatocellular carcinoma patients who failed or were unsuitable for transarterial chemoembolization

Abstract

The role of stereotactic ablative radiotherapy (SABR) in patients with hepatocellular carcinoma (HCC) who are refractory to or unsuitable for transarterial chemoembolization remains unclear. We examined the efficacy and safety of Cyberknife SABR and its effect on survival in this group of HCC patients. From June 2008 to June 2011, 53 patients with 68 tumors of unresectable HCC were treated using Cyberknife SABR. The tumors measured 1.1-13 cm (median, 4.3 cm). The median prescribed dose was 40 Gy in four to five fractions over 4-5 consecutive working days. The median follow-up period was 13.1 months for all patients and 18.1 months for the living patients. Objective responses were observed in 48 of 67 tumors (71.6%), including 22 tumors (32.8%) with complete responses. The 1- and 2-year in-field failure-free rate was 73.3 and 66.8%, respectively. Out-field intrahepatic recurrence was the main cause of treatment failure (28/52 patients). The median survival time was 20.0 months, and the 1- and 2-year overall survival rate was 70.1 and 45.4%, respectively. Multivariable analysis showed that Eastern Cooperative Oncology Group performance status (≤1 vs. >1) and tumor response (responder vs. nonresponder) were independent prognostic factors for overall survival. Radiation-induced liver disease, including classic and nonclassic types, developed in five patients (9.4%). Other acute toxicities were generally mild and tolerable. Our findings supported the feasibility of SABR as a salvage treatment for HCC when transarterial chemoembolization was ineffective or technically unsuitable. Additional efforts to improve the response rate and reduce out-field recurrence are required.