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

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.

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.

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.

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.