All patients visiting the radiation oncologist or the orthopaedic surgeon of participating centres, for possible local treatment of a symptomatic BMLB or impending fracture, will be registered in the OPTIMAL registry. This includes patients with newly diagnosed metastatic bone disease as well as patients undergoing re-treatment of the same lesion or patients who have received previous treatment for other lesions. Preferably patients are included before the start of treatment, but inclusion can also take place during treatment. When patients are already included in the cohort (for treatment of another metastasis), they will not be included a second time when they present with a second lesion of the long bones. This second lesion will be registered under the same patient number.