Samarium-153-EDTMP biodistribution and dosimetry estimation.
Fifty-two patients were treated with single doses of 153Sm-EDTMP in a Phase I escalating dose protocol for palliation of bone pain from metastatic prostate carcinoma. Samarium-153 (T1/2 46.3 hr), maximum beta-particle energies 810 keV (20%), 710 keV (30%), 640 keV (50%), gamma photon 103 keV (28%), was complexed to the tetraphosphonate chelate, EDTMP. Five groups of patients were treated at doses of 1.0, 1.5, 2.0, 2.5, and 3.0 mCi/kg to evaluate toxicity from treatment. Patients were screened prior to treatment and followed after treatment with 99mTc-MDP bone scans. Biodistribution data on this group of patients were acquired and showed rapid uptake of 153Sm-EDTMP into bone with complete clearance of nonskeletal radiotoxicity by 6-8 hr. Also included are complete sets of dosimetry estimations on an additional seven patients who received 0.5 mCi/kg 153Sm-EDTMP Ca++ as part of a multiple dose therapy trial. Estimated radiation absorbed doses to bone surfaces averaged 25,000 mrad/mCi (6686 Gy/MBq), and urinary bladder doses averaged 3600 mrad/mCi (964 Gy/MBq).
Eary
J F
JF
Department of Radiology, University of Washington Medical Center, Seattle 98195.
Collins
C
C
Stabin
M
M
Vernon
C
C
Petersdorf
S
S
Baker
M
M
Hartnett
S
S
Ferency
S
S
Addison
S J
SJ
Appelbaum
F
F
D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy* / Q000556:secondary*; D002614:Chelating Agents / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D009942:Organometallic Compounds / Q000627:therapeutic use*; D009943:Organophosphorus Compounds / Q000627:therapeutic use*; D010166:Palliative Care; D011471:Prostatic Neoplasms / Q000473:pathology*; D011868:Radioisotopes / Q000627:therapeutic use*; D011877:Radionuclide Imaging; D011879:Radiotherapy Dosage; D012493:Samarium / Q000627:therapeutic use*; D013669:Technetium Tc 99m Medronate; D014018:Tissue Distribution
D002614:Chelating Agents; D009942:Organometallic Compounds; D009943:Organophosphorus Compounds; D011868:Radioisotopes; D012493:Samarium; C061972:samarium Sm-153 lexidronam; D013669:Technetium Tc 99m Medronate