title: Estimated human absorbed dose of a new (153)Sm bone seeking agent based on biodistribution data in mice: Comparison with (153)Sm-EDTMP.
abstract: OBJECTIVE
  The main goal in radiotherapy is to deliver the absorbed dose within the target organs in highest possible amount, while the absorbed dose of the other organs, especially the critical organs, should be kept as low as possible. In this work, the absorbed dose to human organs for a new (153)Sm bone-seeking agent was investigated.
  
  
  METHODS
  (153)Sm-(4-{[(bis(phosphonomethyl))carbamoyl]methyl}-7,10-bis(carboxymethyl)-1,4,7,10-tetraazacyclododec-1-yl) acetic acid ((153)Sm-BPAMD) complex was successfully prepared. The biodistribution of the complex was investigated in male Syrian mice up to 48 h post injection. The human absorbed dose of the complex was estimated based on the biodistribution data of the mice by radiation absorbed dose assessment resource (RADAR) method. The target to non-target absorbed dose ratios for (153)Sm-BPAMD were compared with these ratios for (153)Sm-EDTMP.
  
  
  RESULTS
  The highest absorbed dose for (153)Sm-BPAMD was observed in bone surface with 5.828 mGy/MBq. The dose ratios of the bone surface to the red marrow and to the total body for (153)Sm-BPAMD were 5.3 and 20.0, respectively, while these ratios for (153)Sm-EDTMP were 4.4 and 18.3, respectively. This means, for a given dose to the bone surface as the target organ, the red marrow (as the main critical organ) and the total body would receive lesser absorbed dose in the case of (153)Sm-BPAMD.
  
  
  CONCLUSIONS
  Generally, the human absorbed dose estimation of (153)Sm-BPAMD indicated that all other tissues approximately received insignificant absorbed dose in comparison with bone surface and therefore can be regarded as a new potential agent for bone pain palliation therapy.
authors.affiliation: Nuclear Science and Technology Research Institute (NSTRI), Tehran 14155-1339, Iran.
authors.forename: Hassan
authors.initials: H
authors.lastname: Yousefnia
authors.affiliation: Nuclear Science and Technology Research Institute (NSTRI), Tehran 14155-1339, Iran. Electronic address: szolghadri@aeoi.org.ir.
authors.forename: Samaneh
authors.initials: S
authors.lastname: Zolghadri
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000378:metabolism* / Q000528:radiation effects*; D006801:Humans; D008297:Male; D051379:Mice; D009942:Organometallic Compounds / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D009943:Organophosphorus Compounds / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D059408:Pain Management; D011786:Quality Control; D011829:Radiation Dosage; D011868:Radioisotopes; D011874:Radiometry; D012493:Samarium / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D014018:Tissue Distribution
chemical_list: D009942:Organometallic Compounds; D009943:Organophosphorus Compounds; D011868:Radioisotopes; D012493:Samarium; C061972:samarium Sm-153 lexidronam
keywords: BPAMD; Bone pain palliation; Internal dosimetry; RADAR; Sm-153