title: Comparative study of dosimetry between high-dose-rate and permanent prostate implant brachytherapies in patients with prostate adenocarcinoma.
abstract: OBJECTIVE
  To compare the dose coverage, conformity, and homogeneity between high-dose-rate (HDR) brachytherapy and permanent prostate implant (PPI) in the treatment of prostate adenocarcinoma.
  
  
  METHODS
  From January 2003 to August 2004, 54 patients (108 implants) underwent HDR brachytherapy of prostate cancer with iridium-192 stepping source. Of patients who underwent PPI brachytherapy with iodine-125, 72 patients were randomly selected for the purpose of dosimetric comparison. PPI preplan was done based on transrectal ultrasound study, and postplan was done using CT 1 month after implant. Dosimetric parameters of HDR were compared to that of PPI preplan and postplan.
  
  
  RESULTS
  HDR brachytherapy had lower D90 (111.5% vs. 120.2%), lower V100 (97.2% vs. 99.6%), lower natural dose ratio (1.03 vs. 1.13), higher conformal index (0.69 vs. 0.62), and higher homogeneity index (0.63 vs. 0.52) than PPI preplan (all p < 0.0001). All the dosimetric parameters of PPI postplan including D90 (86.7%), V100 (82.0%), natural dose ratio (0.92), conformal index (0.53), and homogeneity index (0.42) were inferior to HDR brachytherapy (all p < 0.0001).
  
  
  CONCLUSIONS
  HDR brachytherapy of the prostate can provide better dose coverage, conformity, and homogeneity compared to PPI.
authors.affiliation: Department of Radiation Oncology, Toronto Sunnybrook Regional Cancer Centre, Toronto, Canada.
authors.forename: Yongjin
authors.initials: Y
authors.lastname: Wang
authors.forename: Raxa
authors.initials: R
authors.lastname: Sankreacha
authors.forename: Adnan
authors.initials: A
authors.lastname: Al-Hebshi
authors.forename: Andrew
authors.initials: A
authors.lastname: Loblaw
authors.forename: Gerard
authors.initials: G
authors.lastname: Morton
mesh_terms: D000230:Adenocarcinoma / Q000532:radiotherapy*; D001918:Brachytherapy / Q000379:methods*; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D007496:Iridium Radioisotopes / Q000627:therapeutic use; D008297:Male; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011874:Radiometry
chemical_list: D007457:Iodine Radioisotopes; D007496:Iridium Radioisotopes