Local effect of stereotactic body radiotherapy for primary and metastatic liver tumors in 130 Japanese patients

BACKGROUND AND AIMS: Stereotactic body radiotherapy (SBRT) is a relatively new treatment for liver tumor. The outcomes of SBRT for liver tumor unfit for ablation and surgical resection were evaluated. METHODS: Liver tumor patients treated with SBRT in seven Japanese institutions were studied retrospectively. Patients given SBRT for liver tumor between 2004 and 2012 were collected. Patients treated with SBRT preceded by trans-arterial chemoembolization (TACE) were eligible. Seventy-nine patients with hepatocellular carcinoma (HCC) and 51 patients with metastatic liver tumor were collected. The median biologically effective dose (BED) (α/β = 10 Gy) was 96.3 Gy for patients with HCC and 105.6 Gy with metastatic liver tumor. RESULTS: The median follow-up time was 475.5 days in patients with HCC and 212.5 days with metastatic liver tumor. The 2-year local control rate (LCR) for HCC and metastatic liver tumor was 74.8% ± 6.3% and 64.2 ± 9.5% (p = 0.44). The LCR was not different between BED(10) ≥ 100 Gy and < 100 Gy (p = 0.61). The LCR was significantly different between maximum tumor diameter > 30 mm vs. ≤ 30 mm (64% vs. 85%, p = 0.040) in all 130 patients. No grade 3 laboratory toxicities in the acute, sub-acute and chronic phases were observed. CONCLUSIONS: There was no difference in local control after SBRT in the range of median BED(10) around 100 Gy for between HCC and metastatic liver tumor. SBRT is safe and might be an alternative method to resection and ablation. SUMMARY: There was no difference in local control after SBRT in the range of median BED(10) around 100 Gy for between HCC and metastatic liver tumor and SBRT is safe and might be an alternative method to resection and ablation.