A new look at radionuclides therapy in metastatic disease of bone (review and prospects).

Bone-seeking radionuclides have been used to treat bone pain due to metastatic bone disease for over 40 years. More than 10 clinical studies using radiostrontium (Sr-89) have shown benefit in about 70-80% of patients having refractory bone pain from prostate, breast and other metastatic bone cancers, with minimal hematological toxicity. Other radionuclides, such as, radiophosphate (P-32), Yttrium-90, lodine-131, Rhenium-186, have also been used. Tumor necrosis has been found within the range of beta irradiation from the surrounding shell of bone incorporating the radionuclide. New strategies using radionuclides may be able to provide more effective methods of treatment, perhaps, beyond palliation. For example, the effect of low dose continuous radiation can be potentiated by hypoxic cell sensitizers. In addition, the kinetics of radionuclide uptake and retention can be modulated to increase the dose of radiation delivered to osteoblastic metastatic lesions, such as osteosarcoma.