title: Bone-seeking radiopharmaceuticals as targeted agents of osteosarcoma: samarium-153-EDTMP and radium-223.
abstract: Osteosarcoma is a cancer characterized by formation of bone by malignant cells. Routine bone scan imaging with Tc-99m-MDP is done at diagnosis to evaluate primary tumor uptake and check for bone metastases. At time of relapse the Tc-99m-MDP bone scan also provides a specific means to assess formation of bone by malignant osteosarcoma cells and the potential for bone-seeking radiopharmaceuticals to deliver radioactivity directly into osteoblastic osteosarcoma lesions. This chapter will review and compare a bone-seeking radiopharmaceutical that emits beta-particles, samarium-153-EDTMP, with an alpha-particle emitter, radium-223. The charged alpha particles from radium-223 have far more mass and energy than beta particles (electrons) from Sm-153-EDTMP. Because radium-223 has less marrow toxicity and more radiobiological effectiveness, especially if inside the bone forming cancer cell than samarium-153-EDTMP, radium-223 may have greater potential to become widely used against osteosarcoma as a targeted therapy. Radium-223 also has more potential to be used with chemotherapy against osteosarcoma and bone metastases. Because osteosarcoma makes bone and radium-223 acts like calcium, this radiopharmaceutical could possibly become a new targeted means to achieve safe and effective reduction of tumor burden as well as facilitate better surgery and/or radiotherapy for difficult to resect large, or metastatic tumors.
authors.affiliation: Levine Children's Hospital, Charlotte, NC, USA, peter.anderson@carolinashealthcare.org.
authors.forename: Peter M
authors.initials: PM
authors.lastname: Anderson
authors.forename: Vivek
authors.initials: V
authors.lastname: Subbiah
authors.forename: Eric
authors.initials: E
authors.lastname: Rohren
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use; D001859:Bone Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D058990:Molecular Targeted Therapy; D009942:Organometallic Compounds / Q000627:therapeutic use*; D009943:Organophosphorus Compounds / Q000627:therapeutic use*; D012516:Osteosarcoma / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000627:therapeutic use*; D011883:Radium / Q000627:therapeutic use*; D013669:Technetium Tc 99m Medronate
chemical_list: D000970:Antineoplastic Agents; D009942:Organometallic Compounds; D009943:Organophosphorus Compounds; D019275:Radiopharmaceuticals; C061972:samarium Sm-153 lexidronam; D011883:Radium; D013669:Technetium Tc 99m Medronate