Curative Irradiation Treatment of Hepatocellular Carcinoma: A Multicenter Phase 2 Trial

Abstract

Purpose: Liver transplantation is the standard definitive treatment for nonmetastatic hepatocellular carcinoma (HCC). However, less than 5% of patients are ultimately candidates as a result of frequent comorbidities and graft shortage. The aim of this study was to evaluate stereotactic body radiation therapy (SBRT) as an ablative treatment for inoperable HCC.

Methods and materials: A prospective phase 2 trial included newly diagnosed single HCC lesions that were without extrahepatic extension and that were deemed unsuitable for standard locoregional therapies, with a tumor size ranging from 1 to 6 cm. The SBRT dose was 45 Gy in 3 fractions. Primary endpoint was the local control of irradiated HCC at 18 months, defined by Response Evaluation Criteria in Solid Tumors.

Results: Forty-three patients were treated and evaluable. Median follow-up was 4.0 years (range, 1.2-4.6 years). All 43 patients had cirrhosis; 37 (88%) were Child-Pugh grade A and 5 (12%) grade B (1 missing data). No patients had received prior local treatment. Thirteen patients (31%) presented grade ≥3 acute adverse events, including 8 patients with an abnormality of the liver function tests (19%). Three patients (10%) experienced a decline in Child-Pugh at 3 months post-SBRT. The 18-month local control rate was 98% (95% confidence interval, 85%-99%). The 18-month overall survival rate was 72% (range, 56%-83%). Median overall survival was 3.5 years.

Conclusions: Local control and overall survival after SBRT for untreated solitary HCC were excellent despite candidates being unfit for transplantation, resection, ablation, or embolization treatments. SBRT should be considered as a bridge to transplant or as definitive therapy for those ineligible for transplant.