A multi-institutional retrospective study of repeated stereotactic body radiation therapy for intra-hepatic recurrent hepatocellular carcinoma

Abstract Purpose Through this multi-institutional study, we aimed to retrospectively evaluate the safety and efficacy of repeated stereotactic body radiation therapy (SBRT) for intra-hepatic recurrent hepatocellular carcinoma (HCC). Materials and methods Between 2005 and 2017, 709 patients with 835 HCCs underwent SBRT; those treated with repeated SBRT were eligible. The median prescribed dose was 40 Gy in 5 fractions. Results Eighty-one patients with 189 tumors underwent repeated SBRT (≥2 courses [median 2 times; range, 2–5 times]). The median follow-up periods from the 1st to 2nd SBRT were 41.5 (range, 12–99) and 20 (range, 1–81) months, respectively. The median interval between the 1st and 2nd SBRT was 18 (range, 3–74) months. The 5-year local recurrence rate was 6.3% (95% confidence interval [CI], 2.3–13.4%). The 5-year overall survival (OS) and liver-related death rates from the 1st SBRT were 60.4% (95% CI, 47.0–73.8%) and 32.9% (95% CI, 20.3–46.0%), respectively, and the 3-year rates from the 2nd SBRT were 61.0% (95% CI, 49.9–75.2%) and 34.5% (95% CI, 20.6–48.9%), respectively. The frequency of grade 3 toxicity was not significantly different between the 1st and 2nd SBRT (1st: 11% [95% CI, 5.2–20%], 2nd: 15% [95% CI, 7.9–24%], p=0.48). Among 39 patients with no intrahepatic recurrence for 1 year after the 1st and 2nd SBRT, the deterioration in liver function following the 1st and 2nd SBRT was not significantly different; the albumin–bilirubin score increased 1 year after the 1st vs. 2nd SBRT (1st: 0.143±0.23, 2nd: 0.195±0.38; p=0.48). Multivariate analysis revealed that the intrahepatic recurrence-free interval was the only significant factor for OS. Conclusion Repeated SBRT for intra-hepatic recurrent HCC resulted in high local control with safety and a satisfactory OS, which were comparable with those of other curative local treatments for patients with well-preserved liver function.