Stereotactic Body Radiotherapy (SBRT) for Pulmonary Metastases in Ewing Sarcoma, Rhabdomyosarcoma, and Wilms Tumors

Inclusion Criteria:

* Diagnosis of Ewing sarcoma, rhabdomyosarcoma, osteosarcoma, non-rhabdomyosarcoma soft tissue sarcoma, Wilms tumor or other primary renal tumor (including clear cell and rhabdoid)
* Age ≤ 21 years;
* Must be capable of treatment without general anesthesia
* Lesion size 8 mm - 3 cm
* Subjects who have lesions within 2 cm of central structures, will be eligible on a case by-case basis
* Pulmonary metastases found at relapse (does not have to be first relapse); no more than 3 lesions per hemi-thorax will be treated but other lesions in the lung may be present
* Greater than 5 weeks from doxorubicin at the time of consent, with radiation to be initiated no less than 6 weeks from doxorubicin
* Informed consent/assent
* Life expectancy \>3 months
* Pulmonary Function FEV1 ≥ 50% of predicted;
* Concurrent immunotherapy is allowed

Exclusion Criteria:

* Prior whole-lung or hemi-thorax irradiation of greater than 12 Gy received less than 6 months prior to consent (focal radiotherapy to the thorax is not an exclusion)
* Lesion larger than 3 cm in diameter
* Patients for whom surgery would be deemed appropriate rather than radiotherapy