Effectiveness of Repeated Stereotactic Body Radiation Therapy for Hepatocellular Carcinoma—Consideration of the Locations of Target Lesions

SIMPLE SUMMARY: Many treatment options are available for hepatocellular carcinoma. Radiation therapy is one of the local options, along with surgery and radiofrequency ablation. Stereotactic body radiation therapy is an effective therapy for hepatocellular carcinoma that provides good outcomes with tolerable toxicities and has been recognized as a local therapy for patients who are ineligible for surgery or radiofrequency ablation. Hepatocellular carcinoma tends to recur, so stereotactic body radiation therapy is also used for recurrent cases. However, few reports have summarized local tumor control, transition of liver function, and side effects in cases of repeated stereotactic body radiation therapy. This study retrospectively evaluated the efficacy of stereotactic body radiation therapy, including repeated radiation therapy, for hepatocellular carcinoma. ABSTRACT: The present study retrospectively evaluated the efficacy of stereotactic body radiation therapy (SBRT), including repeated SBRT, for hepatocellular carcinoma. Participants comprised 220 HCC patients treated with SBRT in Hiroshima University Hospital between December 2008 and December 2021. Median overall survival (OS) and disease-free survival were 52 months (range, 45–64 months) and 17 months (range, 14–23 months), respectively. The 5-year local tumor recurrence rate was 3.4% (95% confidence interval (CI), 1.3–6.9%). Fifty-three patients underwent repeated SBRT (twice, 53 cases; three times, 10 cases; four times, 4 cases; five times, 1 case). Median interval between first and second SBRT was 20 months. Median OS from first SBRT was 76 months (95% CI, 50–102 months). Among patients with repeated SBRT, only one case showed local recurrence after second SBRT. Albumin–bilirubin score increased significantly from 6 to 12 months after repeated SBRT, both in the same segment and in remote segments, but the increase was not significant in the same segment. Only one case of grade 3 bile duct stricture was observed in patients who were treated with repeated SBRT. In conclusion, repeated SBRT provides good local control and a low risk of side effects.