Stereotactic Body Radiotherapy Combined with Sintilimab in Patients with Recurrent or Oligometastatic Hepatocellular Carcinoma: A Phase II Clinical Trial

Abstract

The anti-tumor activity and tolerability of stereotactic body radiotherapy (SBRT) and PD-1 inhibitors have been illustrated in retrospective studies, but the results vary across a broad range. This study aimed to assess the clinical efficacy of SBRT combined with sintilimab in patients with recurrent or oligometastatic hepatocellular carcinoma (HCC). This trial involved patients with recurrent or oligometastatic HCC intravenously treated with SBRT plus sintilimab every 3 weeks for 12 months or until disease progression. The primary endpoint was progression-free survival (PFS). Twenty-five patients were enrolled from August 14, 2019, to August 23, 2021. The median treatment duration was 10.2 months. SBRT was delivered at a median dose of 54 in six fractions. The median follow-up time was 21.9 months, and 32 targeted lesions among 25 patients were evaluated for treatment response according to the Response Evaluation Criteria in Solid Tumors version 1.1. The median PFS was 19.7 months, with PFS rates of 68% and 45.3% at 12 and 24 months, respectively. The median overall survival (OS) was not reached, with OS rates of 91.5% and 83.2% at 12 and 24 months, respectively. The 1- and 2-year local control rate were 100% and 90.9%, respectively. The confirmed objective response rate and disease control rate was 96%, and 96%, respectively. Most adverse events were graded as 1 or 2, and grade 3 adverse events were observed in three patients. SBRT plus sintilimab is an effective, well-tolerated treatment regimen for patients with recurrent or oligometastatic HCC.