Stereotactic Body Radiation Therapy (SBRT) for Hepatocellular Carcinoma: High Rates of Local Control With Low Toxicity.

OBJECTIVES: Stereotactic body radiotherapy (SBRT) is potentially curative treatment for small hepatocellular carcinomas (HCC), but data are limited on its efficacy and toxicity. We hypothesized that SBRT can achieve excellent local control (LC) with acceptable toxicity treating HCC lesions, even in advanced cirrhosis.

MATERIALS AND METHODS: Thirty-seven nonmetastatic HCC patients received SBRT to 43 lesions between October 2012 and April 2016. Median dose was 50 Gy/5 fractions. All Child-Pugh (CP) ≥B patients underwent a planned 1-month break after the first 3 fractions to assess hepatic toxicity. Patients were treated without separately placed fiducial markers using Linac-based SBRT with breath-hold (67%) or 4D-computed tomography with compression belt (33%) to reduce motion. Patients underwent magnetic resonance imaging q3 months post-SBRT.

RESULTS: Median age was 65 (range, 44 to 88). Pre-SBRT mean CP was 6.4 (range, A5 to C11). Nine (24%) had CP≥B8. Thirty-one of 33 patients (93%) had prior liver-directed therapy (median 2). Seventeen (40%) had solitary lesions. Median lesion diameter was 2.7 cm (range, 1.1 to 5.6). Median follow-up was 14 months (range, 2 to 45). There was 1 local failure (multifocal HCC with 3 prior transarterial chemoembolization). LC, freedom from liver progression, and overall survival at 12 months was 95%, 66%, 87% in the full cohort, and 100%, 76%, 93% for patients with solitary lesions. Four had grade 3 toxicity (ascites [n=2]/gastrointestinal bleed [n=1]/capsular pain [n=1]). Eight of 9 CP≥B8 patients had no grade ≥3 hepatic toxicity.

CONCLUSIONS: SBRT for HCC is well-tolerated even in patients with advanced cirrhosis and prior liver-directed treatment and provides excellent LC even for larger lesions that cannot be controlled with radiofrequency ablation. LC with SBRT compares favorably to other liver-directed therapies. Prospective studies comparing SBRT with other liver-directed therapies are warranted.