Stereotactic body radiotherapy combined with sintilimab in patients with recurrent or oligometastatic hepatocellular carcinoma: A phase II clinical trial.

Background: Stereotactic body radiotherapy (SBRT) and programmed cell death 1 inhibitors have shown potential in treating hepatocellular carcinoma (HCC) in retrospective studies.

Aim: To evaluate the efficacy of combining SBRT with sintilimab for patients with recurrent or oligometastatic HCC.

Methods: This trial involved patients with recurrent or oligometastatic HCC intravenously treated with SBRT plus sintilimab every 3 wk for 12 mo or until disease progression. The primary endpoint was progression-free survival (PFS).

Results: Twenty-five patients were enrolled from August 14, 2019, to August 23, 2021. The median treatment duration was 10.2 (range, 0.7-14.6) months. SBRT was delivered at a median dose of 54 (range, 48-60) Gy in 6 (range, 6-10) fractions. The median follow-up time was 21.9 (range, 10.3-39.7) mo, 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 mo [95% confidence interval (CI): 16.9-NA], with PFS rates of 68% (95%CI: 52-89) and 45.3% (95%CI: 28-73.4) at 12 and 24 mo, respectively. The median overall survival (OS) was not reached, with OS rates of 91.5% (95%CI: 80.8-100.0) and 83.2% (95%CI: 66.5-100.0) at 12 and 24 mo, respectively. The 1- and 2-year local control rate were 100% and 90.9% (95%CI: 75.4%-100.0%), 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.

Conclusion: SBRT plus sintilimab is an effective, well-tolerated treatment regimen for patients with recurrent or oligometastatic HCC.