Stereotactic body radiotherapy in patients with hepatocellular carcinoma in a multimodal treatment setting.

Purpose: Retrospective evaluation of stereotactic body radiation therapy (SBRT) in patients with hepatocellular carcinoma (HCC).

Methods: We retrospectively analyzed 36 patients (45 lesions) treated between 2011 and 2017. Twenty-seven had previous treatments. Current treatment consisted of SBRT alone (n = 15) or selective transarterial chemoembolization (TACE) followed by SBRT to the same lesions (n = 21). Eight patients received additional local treatments to different lesions. Liver function was predominantly moderately restricted (Child A: 29, Child B: 6, Child C: 1). Treatment planning was based on 4D-computed tomography, dose/fractionation varied depending on location and size, most commonly 3 fractions of 12.5 Gy (65% isodose) and 5 fractions of 8 Gy (80% isodose).

Results: Median follow-up was 15 months. Local recurrence was observed in 3 lesions (7%), resulting in 1‑and 2‑year local control rates of 93%. The only significantly predicting factor was the use of abdominal compression. New hepatic lesions occurred in 19 patients (52%), 1‑ and 2‑year freedom-from-hepatic-failure (FFHF) was 39% and 32%, respectively. Only the number of treated lesions was predictive for FFHF. Sixteen patients have died, resulting in 1‑ and 2‑year overall survival (OS) of 64% and 41%, respectively, significantly impacted by the number of treated lesions and Child-Pugh class. Severe acute and late toxicity (≥grade 3) was observed in 3% and 8%, respectively. 6 patients (17%) received liver transplantation (OLT) after SBRT, of whom 5 showed pathological complete remission.

Conclusion: SBRT (±TACE) in highly pretreated HCC is effective and associated with excellent LC and low toxicity. SBRT may be used as definitive or bridging treatment prior to OLT. Patients with multifocal lesions have significantly decreased 1‑ and 2‑year FFHF and OS.