Thermal Ablation Versus Stereotactic Body Radiotherapy After Transarterial Chemoembolization for Inoperable Hepatocellular Carcinoma: A Propensity Score-Weighted Analysis

BACKGROUND. Transarterial chemoembolization (TACE) has synergistic properties when combined with ablative therapies for hepatocellular carcinoma (HCC). OBJECTIVE. The purpose of our study was to compare outcomes for inoperable HCC between TACE with percutaneous thermal ablation (TACE-TA) and TACE with stereotactic body radiotherapy (TACE-SBRT) using propensity score-weighted cohorts. METHODS. This retrospective study included 190 patients with a single inoperable HCC treated from 2007 to 2018 by either TACE-SBRT (n = 90) or TACE-TA (n = 100). The primary outcome was overall survival (OS). Secondary outcomes included progression-free survival (PFS) and hepatotoxicity (defined as Child-Pugh score elevation of ≥ 2 within 2-6 months after treatment). Fine-Gray competing risk models with propensity score weighting and transplant as the competing risk factor were used to model OS and PFS. RESULTS. The median follow-up time was 48.2 months. Both OS and PFS were significantly higher for TACE-TA (77% and 76%, respectively, at 2 years) than TACE-SBRT (49% and 50%, respectively, at 2 years) in the propensity score-weighted multivariate model (OS: subdistribution hazard ratio [sHR] = 2.70, p < .001; PFS: sHR = 1.71, p = .02). Treatment-related hepatotoxicity occurred in 9% of patients who underwent TACE-TA versus 27% of those who underwent TACE-SBRT (p = .01). For the subset of patients with Barcelona Clinic Liver Cancer A HCC and Child-Pugh A cirrhosis (TACE-SBRT, n = 36 patients; TACE-TA, n = 55 patients), OS (p = .11) and PFS (p = .19) were not significantly different between the two treatment modalities. CONCLUSION. Compared with TACE-SBRT, TACE-TA showed superior OS and PFS, possibly from its lesser hepatotoxicity. The two strategies did not differ in OS and PFS for patients with the earliest-stage HCC and preserved liver function. CLINICAL IMPACT. Across all patients, TACE-TA may be superior to TACE-SBRT for inoperable HCC.