High versus low dose Stereotactic Body Radiation Therapy for hepatic metastases

•SBRT for liver metastases is a safe alternative for surgical resection or ablation.•High dose (>100 Gy) SBRT provides better local control than low dose (≤100 Gy) SBRT.•Toxicity rates of SBRT are low and do not increase after dose escalation.•Dose escalation is positively associated with overall survival. Stereotactic Body Radiation Therapy (SBRT) is a treatment option for patients with liver metastases. This study evaluated the impact of high versus low dose image-guided SBRT of hepatic metastases. This is a single-center retrospective study of patients with liver metastases treated with SBRT. For analyses, patients were divided into two groups: ≤100 Gy and >100 Gy near-minimum Biological Effective Doses (BED98%). The main outcomes were local control (LC), toxicity and overall survival (OS). Cox regression analyses were performed to determine prognostic variables on LC and OS. Ninety patients with 97 liver metastases (77% colorectal) were included. Median follow-up was 28.6 months. The two-year LC rates in the ≤100 Gy and >100 Gy BED98% group were 60% (CI: 41–80%) and 90% (CI: 80–100%), respectively (p = 0.004). Grade 3 toxicity occurred in 7% vs 2% in the ≤100 Gy and >100 Gy group (p = 0.23). Two-year OS rates in the ≤100 Gy and >100 Gy group were 48% (CI: 32–65%) and 85% (CI: 73–97%), respectively (p = 0.007). In multivariable Cox regression analyses, group dose and tumor volume were significantly correlated with LC (HR: 3.61; p = 0.017 and HR: 1.01; p = 0.005) and OS (HR: 2.38; p = 0.005 and HR: 1.01; p =