Can a new radiation method tackle multiple tumors at once?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Documented informed consent of the participant and/or legally authorized representative * Assent, when appropriate, will be obtained per institutional guidelines * Age: \>= 18 years * Karnofsky performance status \> 60 * Poly-metastatic disease, \> 5 lesions, and with at least one lesion \> 2.0 cm, with limited treatment options, and ineligible for or in progression under the standard systemic therapy * Pre-screening assessment confirms that the intervention can be administered without exceeding dose constraint guidelines * Patients with brain metastases can be included but brain metastases must be treated prior to enrollment and follow up magnetic resonance imaging (MRI) 3 months after treatment shows stable findings * Spinal cord metastases are allowed as long as treatment with or without radiation is completed * Prior radiotherapy in general is allowed, as long as the composite plan meets dose constraints * Life expectancy \>= 3 months in the opinion of the treating investigators * Off systemic therapy for at least one month prior and one month after study intervention Exclusion Criteria: * Judgement by the investigator that the patient is unsuitable to participate in the study and the patient is unlikely to comply with study procedures, restrictions, and requirements * Those not eligible for SBRT after review by a radiation oncologist * Serous medical comorbidities precluding radiotherapy * Unable to undergo a CT scan * Pregnant and/or breastfeeding women are excluded from this study as these agents may have the potential for teratogenic or abortifacient effects. Female patients of childbearing potentially must have a negative urine or serum pregnancy test within 72 hours prior to receiving therapy * On active systemic therapy * Prospective participants who, in the opinion of the investigator, may not be able to comply with all study procedures (including compliance issues related to feasibility/logistics)