Stereotactic Body Radiotherapy (SBRT) for liver metastasis – clinical outcomes from the international multi-institutional RSSearch® Patient Registry

Abstract

BackgroundStereotactic body radiotherapy (SBRT) is an emerging treatment option for liver metastases in patients unsuitable for surgery. We investigated factors associated with clinical outcomes for liver metastases treated with SBRT from a multi-center, international patient registry.MethodsPatients with liver metastases treated with SBRT were identified in the RSSearch® Patient Registry. Patient, tumor and treatment characteristics associated with treatment outcomes were assessed. Dose fractionations were normalized to BED10. Overall survival (OS) and local control (LC) were evaluated using Kaplan Meier analysis and log-rank test.ResultsThe study included 427 patients with 568 liver metastases from 25 academic and community-based centers. Median age was 67 years (31–91 years). Colorectal adenocarcinoma (CRC) was the most common primary cancer. 73% of patients received prior chemotherapy. Median tumor volume was 40 cm3 (1.6–877 cm3), median SBRT dose was 45 Gy (12–60 Gy) delivered in a median of 3 fractions [1–5]. At a median follow-up of 14 months (1–91 months) the median overall survival (OS) was 22 months. Median OS was greater for patients with CRC (27 mo), breast (21 mo) and gynecological (25 mo) metastases compared to lung (10 mo), other gastro-intestinal (GI) (18 mo) and pancreatic (6 mo) primaries (p < 0.0001). Smaller tumor volumes (< 40 cm3) correlated with improved OS (25 months vs 15 months p = 0.0014). BED10 ≥ 100 Gy was also associated with improved OS (27 months vs 15 months p < 0.0001). Local control (LC) was evaluable in 430 liver metastases from 324 patients. Two-year LC rates was better for BED10 ≥ 100 Gy (77.2% vs 59.6%) and the median LC was better for tumors < 40 cm3 (52 vs 39 months). There was no difference in LC based on histology of the primary tumor.ConclusionsIn a large, multi-institutional series of patients with liver metastasis treated with SBRT, reasonable LC and OS was observed. OS and LC depended on dose and tumor volume, while OS varied by primary tumor. Future prospective trials on the role of SBRT for liver metastasis from different primaries in the setting of multidisciplinary management including systemic therapy, is warranted.Trial registrationClinicaltrials.gov: NCT01885299.

Historical perspective: Two decades of progress in treating metastatic colorectal cancer

“…Median overall survival for colorectal cancer liver metastases after SBRT was 27 months in a retrospective review of the RSS Patient Registry. Several studies have examined small numbers of patients with hepatic metastases of varying primary tumors in the past; this is a larger series that allowed for the subgroup analysis by histology . Future prospective studies investigating the role of SBRT in the treatment of colorectal liver metastases will better inform future management.…”

“…Several studies have examined small numbers of patients with hepatic metastases of varying primary tumors in the past; this is a larger series that allowed for the subgroup analysis by histology. 179 Future prospective studies investigating the role of SBRT in the treatment of colorectal liver metastases will better inform future management. The role of RFA for the treatment of liver metastases also warrants further investigation.…”

Radiomics for liver tumours

“…With the introduction of image guidance and conformal radiotherapy techniques, the treatment of both primary and secondary liver tumours has experienced significant improvement over the past few years, leading to increased local control rates and decreased normal tissue toxicity [14][15][16][17][18][19].…”

Structure guided deformable image registration for treatment planning CT and post stereotactic body radiation therapy (SBRT) Primovist® (Gd‐EOB‐DTPA) enhanced MRI

“…Stereotactic Body Radiation Therapy (SBRT) is an ablative technique characterized by the high dose delivered in one to five fractions with either the same or greater biologically effective dose as conventional radiotherapy . Studies have shown appreciable local control with the use of SBRT in primary and metastatic hepatic malignancies . SBRT has become the selected treatment of choice for patients who are not candidates for surgery due to tumor location .…”