The Role of Stereo-tActic BoDy RadIotherApy iN Oligo-Progressive MalignanT Disease

Systemic therapy is the main treatment for patients with metastatic cancers. Oligo-progression has become a recognized entity for metastatic cancer and it is thought that a subset of cancer cells may develop heterogeneity and resistant clones while receiving systemic therapy. This results in overall tumor response but progression in metastatic sites. Current standard is to change systemic therapies. With advancing technologies, stereotactic body radiation therapy is being used to deliver high doses of focused radiation to the disease site, while minimizing risk of injury to the surrounding organs. SBRT is increasingly being used in patients presenting oligo-metastatic disease, and is recognized as having a potential for cure. This study will investigate the use of SBRT for breast and genito-urinary cancer patients with oligo-progression. Patients will be seen before and at the end of treatment and will be followed at 4 month intervals for up to 2 years. During the visits participants will complete quality of life questionnaires and will have standard of care imaging. Patients will also have the option to provide blood at baseline, during treatment, and at various follow up time points for analysis of ctDNA