Various single or multi-modality therapeutic options are available to treat pain of bone metastasis in patients with prostate cancer.Different radionuclides that emitβ-rays such as 153Samarium and 89Strontium and achieve palliation are commercially available.In contrast toβ-emitters,223Radium as a a-emitter has a short path-length.The advantage of the a-emitter is thus a highly localized biological effect that is caused by radiation induced DNA double-strand breaks and subsequent cell killing and/or limited effectiveness of cellular repair mechanisms.Due to the limited range of the a-particles the bone surface to red bone marrow dose ratio is also lower for 223Radium which is expressed in a lower myelotoxicity.The a emitter 223Radium dichloride is the first radiopharmaceutical that significantly prolongslife in castrate resistant prostate cancer patients with wide-spread bone metastatic disease.In a phaseⅢ,randomized,double-blind,placebo-controlled study 921patients with castration-resistant prostate cancer and bone metastases were randomly assigned.The analysis confirmed the 223Radium survival benefit compared to the placebo(median,14.9 mo vs 11.3 mo;P<0.001).In addition,the treatment results in pain palliation and thus,improved quality of life and a delay of skeletal related events.At the same time the toxicity profile of223Radium was favourable.Since May 2013,223Radium dichloride(Xofigo?)is approved by the US Food and Drug Administration. Various single or multi-modality therapeutic options are available to treat pain of bone metastasis in patients with prostate cancer. Different radionuclides that emit beta-rays such as 153 Samarium and 89 Strontium and achieve palliation are commercially available. In contrast to beta-emitters, 223 Radium as a a -emitter has a short path-length. The advantage of the a-emitter is thus highly localized biological effect that is caused by radiation induced DNA double-strand breaks and subsequent cell killing and / or limited effectiveness of cellular repair mechanisms. D to the limited range of the a-particles the bone surface to red bone marrow dose ratio is also lower for 223Radium which is expressed in a lower myelotoxicity The a emitter 223Radium dichloride is the first radiopharmaceutical that significantly prolongslife in castrate resistant prostate cancer patients with wide -spread bone metastatic disease. In a phase III, randomized, double-blind, placebo-controlled study 921 patients with castration -resistant prostate cancer and bone metastases were randomly assigned. The analysis confirmed the 223Radium survival benefit compared to the placebo (median, 14.9 mo vs 11.3 mo; P <0.001). Addition, the treatment results in pain palliation and thus, improved quality of life and a delay of skeletal related events. At the same time the toxicity profile of 223Radium was favourable .ince May 2013,223Radium dichloride (Xofigo®) is approved by the US Food and Drug Administration.