title: Quantitative bone single-photon emission computed tomography for prediction of pain relief in metastatic bone disease treated with rhenium-186 etidronate.
abstract: OBJECTIVE
  To calculate radiation doses of rhenium-186 ((186)Re) etidronate in painful bone metastases using quantitative bone single-photon emission computed tomography (SPECT) and to determine the threshold dose for predicting pain relief. We also wanted to determine whether technetium-99m ((99m)Tc) methylene diphosphonate (MDP) concentrations predict radiation doses of (186)Re etidronate in painful lesions.
  
  
  METHODS
  Forty-eight patients with breast and prostate cancer were evaluated. Patients received therapeutic doses of (186)Re etidronate. The area under the pain over time curve (AUPC) was measured for 8 weeks after treatment. Response was calculated as the percentage of change in AUPC. Quantitative bone SPECT (QBS)-measured concentration of (186)Re etidronate was used for calculating radiation doses. Receiver operating characteristics curve analysis determined the radiation dose threshold that best separated responders from nonresponders. SPECT-measured concentration of (186)Re etidronate in the urinary bladder was correlated with its concentration in the voided urine. Concentration of (99m)Tc MDP was compared with radiation doses to painful metastases.
  
  
  RESULTS
  The radiation dose threshold was 2.10 Gy. For a decrease of 50% in the AUPC, the positive predictive value (PPV) of this value was 75% and the negative predictive value (NPV) was 88%. For a decrease in pain of 33%, the PPV was 84% and the NPV was 81%. In prostate cancer patients only, the PPV was 81% and the NPV was 92%. The correlation between in vivo/in vitro measured urine concentration was 0.90. The correlation between (99m)Tc MDP concentration and radiation doses of (186)Re etidronate was 0.92.
  
  
  CONCLUSIONS
  QBS-measured radiation doses of (186)Re etidronate in painful metastases are a good predictor of pain relief. Bone SPECT using (99m)Tc MDP predicts radiation doses delivered by (186)Re etidronate.
authors.affiliation: Departments of Nuclear Medicine, Oncology, and Neurology, Rambam Medical Center, Haifa, Israel. drisrael@netvision.net.il
authors.forename: O
authors.initials: O
authors.lastname: Israel
authors.forename: Z
authors.initials: Z
authors.lastname: Keidar
authors.forename: R
authors.initials: R
authors.lastname: Rubinov
authors.forename: G
authors.initials: G
authors.lastname: Iosilevski
authors.forename: A
authors.initials: A
authors.lastname: Frenkel
authors.forename: A
authors.initials: A
authors.lastname: Kuten
authors.forename: L
authors.initials: L
authors.lastname: Betman
authors.forename: G M
authors.initials: GM
authors.lastname: Kolodny
authors.forename: D
authors.initials: D
authors.lastname: Yarnitsky
authors.forename: D
authors.initials: D
authors.lastname: Front
mesh_terms: D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy / Q000556:secondary; D001943:Breast Neoplasms / Q000473:pathology; D004307:Dose-Response Relationship, Radiation; D012968:Etidronic Acid / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009942:Organometallic Compounds / Q000627:therapeutic use*; D010146:Pain / Q000209:etiology / Q000532:radiotherapy*; D010147:Pain Measurement; D010166:Palliative Care; D011471:Prostatic Neoplasms / Q000473:pathology; D012372:ROC Curve; D019275:Radiopharmaceuticals / Q000627:therapeutic use*; D011879:Radiotherapy Dosage; D013669:Technetium Tc 99m Medronate; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D009942:Organometallic Compounds; D019275:Radiopharmaceuticals; C064573:rhenium-186(tin)etidronate; D012968:Etidronic Acid; D013669:Technetium Tc 99m Medronate