Ablative Radiosurgery vs Stereotactic RT in 5 Fractions With SIB for Oligometastatic Bone Lesions

Inclusion Criteria: * Performance status ECOG ≤2 * Life expectancy \> 6 months according to Mizumoto criteria\* * Oligometastatic disease (Total number of metastases from 1 to 5: both synchronous and metachronous with maximum involvement of three organs in total - lymph nodes, bones, lungs, liver, adrenal gland, brain- with known histology * At least one bone metastasis treatable with SABR or SRS * Each secondary localization (synchronous, metachronous or oligoprogressive) must be treated with radical intent. * Patients may have received other anticancer treatments (surgery for initial site of disease or other metastases, chemotherapy, radiotherapy for other metastatic sites) Exclusion Criteria: * Sites of disease not eligible for stereotactic radiotherapy * Serious medical comorbidities that preclude RT * Overlap with a previously treated volume of radiotherapy * Dimension greater than 5 cm for extra-cranial lesions. * Size greater than 3 cm for brain lesions * More than 1 brain metastases * Clinical or radiological evidence of spinal cord compression or epidural tumor within 2mm of the spinal cord * Radiological evidence of vertebral body fracture or involvement of more than 40% of the vertebral body * Radiological evidence of cortical involvement in long bones * Pregnant or breastfeeding women