Stereotactic ablative radiation therapy shows promise in treating extracranial sarcoma metastases

Stereotactic ablative radiation therapy (SABR) shows promise in treating extracranial sarcoma metastases, according to a study that suggests that age and the distinction between lung and non-lung metastases are important prognostic factors for overall survival (OS).

The study identified a total of 94 patients with 118 lesions, predominantly located in the lung (77), non-spinal bone (15), and spine (10). The median biologically effective dose (BED4) administered was 175 Gy4, with a median dose/fractionation schedule of 50 Gy/5 fractions.

The results indicated promising 1- and 2-year OS rates of 81.3% and 50.5%, respectively. Cox proportional hazards multivariate analysis found that advanced age and non-lung metastases were associated with inferior OS (P < 0.03). Patients with 0-2 of these risk factors exhibited estimated 2-year OS rates of 65.1%, 38.9%, and N/A, respectively.

For local control, 1- and 2-year rates were reported at 85.3% and 78.2%, respectively. Cox proportional hazards multivariate analysis identified BED4<175 Gy as the only factor associated with inferior local control. Importantly, only 10 out of 118 treated lesions experienced treatment-related toxicities, all classified as Grade 1-2.

Reference
Singh R, Konrad A, Roubil JG, et al. Improved Local Control following Dose-Escalated Stereotactic Ablative Radiation Therapy (SABR) for Metastatic Sarcomas: An International Multi-Institutional Experience. Radiother Oncol. 2023;110020. doi: 10.1016/j.radonc.2023.110020. Epub ahead of print. PMID: 38007042.