 The primary goal of the study is to determine the local control-rate after radiotherapy RT with and without simultaneous integrated boost SIB concepts in patients with bone metastases of the spine. Further study objectives are survival, and clinical parameters such as pain, quality of life QoL and fatigue. We expect an improvement in local control and consecutively an increased re-sclerotization of the bone metastasis due to a higher biological dose in the tumor area. Therefore patients could benefit in quality-of-life, pain relief and mobility. 