Palliative treatment of metastatic bone pain with radiopharmaceuticals: A perspective beyond Strontium-89 and Samarium-153.

PURPOSE The present review article aims to provide an overview of the available radionuclides for palliative treatment of bone metastases beyond (89)Sr and (153)Sm. In addition, it aims to review and summarize the clinical outcomes associated with the palliative treatment of bone metastases using different radiopharmaceuticals. MATERIALS AND METHODS A literature search was conducted on Science Direct and PubMed databases (1990 - 2015). The following search terms were combined in order to obtain relevant results: "bone", "metastases", "palliative", "care", "therapy", "treatment", "radiotherapy", "review", "radiopharmaceutical", "phosphorus-32", "strontium-89", "yttrium-90", "tin-117m", "samarium-153", "holmium-166", "thulium-170", "lutetium-177", "rhenium-186", "rhenium-188" and "radium-223". Studies were included if they provided information regarding the clinical outcomes. RESULTS AND CONCLUSIONS A comparative analysis of the measured therapeutic response of different radiopharmaceuticals, based on previously published data, suggests that there is a lack of substantial differences in palliative efficacy among radiopharmaceuticals. However, when the comparative analysis adds factors such as patient's life expectancy, radionuclides' physical characteristics (e.g. tissue penetration range and half-life) and health economics to guide the rational selection of a radiopharmaceutical for palliative treatment of bone metastases, (177)Lu and (188)Re-labeled radiopharmaceuticals appear to be the most suitable radiopharmaceuticals for treatment of small and medium/large size bone lesions, respectively.