Rationale: Bone metastases arise in 50% of all patients dying of cancer, increasing up to 70% in patients with breast and prostate cancer. The lesions can cause pain and fractures, leading to diminished quality of life and poorer survival. Current knowledge concerning adequate, personalized treatment of metastatic lesions of the long bones in patients with disseminated cancer is insufficient and inconclusive due to lack of large, prospective series with patient reported outcome measures. One of the debatable issues is the effectiveness of postoperative radiotherapy. It has become common practise due to professional opinion, but research evidence is lacking. It is thought that adjuvant radiotherapy improves the durability of an implant, prevents progression of the lesion, promotes bone healing, improves limb function, minimises pain and reduces the need for reoperations, however none of these are certain. Moreover, it is a burden on patient's quality of life (e.g. multiple extra hospital visits) causing toxicity and possible side effects (e.g. skin irritation). The true beneficial effect, weighing up the possible pros and certain cons, of adjuvant radiotherapy is thus unknown.