title: Pharmacokinetics of rhenium-186 after administration of rhenium-186-HEDP to patients with bone metastases.
abstract: The pharmacokinetics of 186Re-HEDP, a radiopharmaceutical for palliative treatment of metastatic bone pain, was investigated in 11 patients (17 studies) who suffered from metastatic breast or prostate cancer. Half-life times of 186Re in three blood fractions (whole blood, plasma and plasma water) were 40.1 +/- 5.0, 41.0 +/- 6.0 and 29.5 +/- 6.4 hr, respectively. Time-dependent increase in plasma-protein binding was observed, probably caused by in vivo decomposition of 186Re-HEDP. Total urinary 186Re excretion was 69% +/- 15%, of which 71% +/- 6% was excreted in the first 24 hr after injection. The BSI (i.e., fraction of the skeleton showing scintigraphic evidence of metastatic disease) closely correlated with the fraction of dose non-renally cleared (r = 0.98). This implies that the amount of radioactivity taken up by the skeleton and hence the bone marrow absorbed dose can be predicted from a diagnostic pre-therapy 99mTc-HDP scintigram. The pharmacokinetic behavior indicates that 186Re-HEDP has suitable properties to justify its application.
authors.affiliation: Department of Nuclear Medicine, University Hospital Utrecht, The Netherlands.
authors.forename: J M
authors.initials: JM
authors.lastname: de Klerk
authors.forename: A
authors.initials: A
authors.lastname: van Dijk
authors.forename: A D
authors.initials: AD
authors.lastname: van het Schip
authors.forename: B A
authors.initials: BA
authors.lastname: Zonnenberg
authors.forename: P P
authors.initials: PP
authors.lastname: van Rijk
mesh_terms: D000368:Aged; D001859:Bone Neoplasms / Q000532:radiotherapy / Q000556:secondary*; D001943:Breast Neoplasms / Q000503:physiopathology; D012968:Etidronic Acid / Q000627:therapeutic use*; D005260:Female; D006207:Half-Life; D006801:Humans; D008297:Male; D008875:Middle Aged; D010166:Palliative Care / Q000379:methods*; D011471:Prostatic Neoplasms / Q000503:physiopathology; D011868:Radioisotopes / Q000627:therapeutic use*; D012211:Rhenium / Q000493:pharmacokinetics / Q000627:therapeutic use*
chemical_list: D011868:Radioisotopes; D012211:Rhenium; D012968:Etidronic Acid