294 - Stereotactic Body Radiation Therapy vs. Radiofrequency Ablation for Small (=2 cm) HCCs: Interim Results from a Prospective, Single-Center, Non-Inferiority Randomized Clinical Trial

02:25pm - 02:35pm ET

Room 254

Presenter(s)

Lihong Wang, MD - The First affiliated Hospital Zhejiang University School of Medicine, Hangzhou, Zhejiang

L. Wang¹, W. Li¹, X. Zhu¹, D. Yan¹, T. Jiang², S. Yan¹, and T. Liang³; ¹Department of Radiation Oncology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China, ²Department of Ultrasound, The First Affiliated Hospital, College of Medicine, Zhejiang University, HangZhou, Zhejiang, China, ³Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, HangZhou, Zhejiang, China

Purpose/Objective(s):

To prospectively compare the efficacy and safety of stereotactic body radiation therapy (SBRT) versus radiofrequency ablation (RFA) for single hepatocellular carcinomas (HCC) =2 cm, and to test the non-inferiority of SBRT with respect to 2-year local progression-free survival (LPFS).

Materials/Methods: This single-center, randomized controlled trial enrolled patients with solitary HCC =2 cm deemed suitable for either SBRT or RFA. Eligible participants were randomized 1:1 to SBRT (50 Gy in five fractions delivered via image-guided radiotherapy) or RFA (ultrasonography-guided percutaneous ablation). The primary endpoint was 2-year LPFS, defined as the proportion of living subjects without local tumor progression at 2 years of follow-up. Secondary endpoints included progression-free survival (PFS), overall survival (OS), local control rate (LCR), and treatment-related toxicity. The Clopper-Pearson methodology was used to calculate the two-sided 95% CI for survival rate,and the Miettinen-Nurminen method methodology was used to calculate the two-sided 95% CI for all rate difference.

Results:

A total of 93 patients (47 SBRT; 46 RFA) with solitary HCC =2 cm were enrolled between November 2020 and February 2024. Baseline demographics, liver function, and tumor characteristics were well balanced between groups. After a median follow-up of 30.0 months (IQR 18.0–35.0), the 2-year LPFS rates were 91.5% (95% CI = 83.5–99.5%) for SBRT and 87.0% (95% CI = 77.2–96.7%) for RFA. The difference in rates (SBRT–RFA) was 4.5% (95% CI = -9.0–18.6%), meeting the non-inferiority criteria. LCRs at 1 and 2 years were comparable between groups. The median PFS was not reached in the SBRT arm, while it was 41 months in the RFA arm (HR = 0.57, 95% CI 0.28–1.19; P = 0.13). Two-year OS was 97.9% for SBRT and 97.8% for RFA. Subgroup analysis indicated a potential LPFS benefit for SBRT in tumors adjacent to major vessels (HR = 0.09; P = 0.04). Any-grade acute toxicity occurred in 36.2% of patients in the SBRT group and 32.6% in the RFA group, with no significant difference (P = 0.72).

Conclusion:

For patients with single HCC =2 cm, SBRT is non-inferior to RFA in terms of efficacy and safety. These findings support SBRT as a non-invasive alternative to RFA for small HCCs, and suggest that patient-specific factors such as tumor location may guide treatment selection, potentially improving both oncological and patients’ reported outcomes in HCC management. (ChiCTR2000039404)