The OPTIMAL Study in its entirety aims to provide a more personalized treatment for metastases in the long bones based on expected survival and impending fracture risk in order to improve functioning and the quality of life for the remaining lifetime in patients with disseminated cancer. The OPTIMAL Study will provide the infrastructure for a prospective cohort (OPTIMAL cohort) and multiple independent trials. The specific aims of the cohort are discussed in this protocol. The objectives and plan of the first trial (Post-Operative Radiotherapy; PORT study) are discussed in a separate protocol.