High Dose Radiotherapy for Palliation (Hi-D)

5.1. Inclusion Criteria Subjects must meet all of the following criteria to be eligible for participation in this study: * Age 18 or older. * Able to provide informed consent * Patient has histologically confirmed solid tumour malignancy * ECOG performance status 0 - 2 * Life Expectancy \> 6 months * Locally advanced or metastatic disease with 1-3 target lesions larger than 5cm in minimum dimension, with no more than 2 target lesions in a single organ; patients can have any number of non-target lesions * A history and physical exam, including ECOG performance status, performed within 6 weeks prior to trial enrollment * Not suitable for or declined curative-intent treatment * Subject has had a CT chest, abdomen and pelvis or PET-CT within 8 weeks prior to enrollment, and with 12 weeks of treatment * MRI spine for patients receiving RT to vertebral or paraspinal metastases * Patient is judged able to: * Maintain a stable position during therapy * Tolerate immobilization device(s) that may be required to deliver radiation safely 5.2. Exclusion Criteria Subjects are excluded from the study if any of the following criteria apply: * Hematologic malignancy * Disease limited to intracranial sites * Serious medical co-morbidities precluding radiotherapy * Prior radiation to target lesion that precludes delivery of repeat radiation. All such cases should be discussed with the local and study PIs. * Pregnant people