title: The biochemical recurrence-free rate in patients who underwent prostate low-dose-rate brachytherapy, using two different definitions.
abstract: BACKGROUND
  To assess the biochemical recurrence (BCR)-free rate in patients who underwent prostate low-dose-rate brachytherapy (LDR-brachytherapy), using two different definitions (Phoenix definition and PSA ≥ 0.2 ng/mL).
  
  
  METHODS
  Two hundreds and three patients who were clinically diagnosed with localized prostate cancer (cT1c-2cN0M0) and underwent LDR-brachytherapy between July 2004 and September 2008 were enrolled. The median follow-up period was 72 months. We evaluated the BCR-free rate using the Phoenix definition and the PSA cut-off value of 0.2 ng/mL, as in the definition for radical prostatectomy. To evaluate an independent variable that can predict BCR, Cox's proportional hazard regression analysis was carried out.
  
  
  RESULTS
  The BCR-free rate in patients using the Phoenix definition was acceptable (5-year: 92.8%). The 5- year BCR-free rate using the strict definition (PSA ≥ 0.2 ng/mL) was 74.1%. Cox's proportional hazard regression analysis showed that a higher biological effective dose (BED) of ≥180 Gy2 was the only independent variable that could predict BCR (HR: 0.570, 95% C.I.: 0.327-0.994, p = 0.048). Patients with a higher BED (≥180 Gy2) had a significantly higher BCR-free rate than those with a lower BED (<180 Gy2) (5-year BCR-free rate: 80.5% vs. 67.4%).
  
  
  CONCLUSIONS
  A higher BED ≥180 Gy2 promises a favorable BCR-free rate, even if the strict definition is adopted.
authors.affiliation: Department of Urology, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan. sendo@naramed-u.ac.jp.
authors.forename: Nobumichi
authors.initials: N
authors.lastname: Tanaka
authors.forename: Isao
authors.initials: I
authors.lastname: Asakawa
authors.forename: Emiko
authors.initials: E
authors.lastname: Katayama
authors.forename: Akihide
authors.initials: A
authors.lastname: Hirayama
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Hasegawa
authors.forename: Noboru
authors.initials: N
authors.lastname: Konishi
authors.forename: Kiyohide
authors.initials: K
authors.lastname: Fujimoto
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy; D015331:Cohort Studies; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000097:blood* / Q000175:diagnosis*; D009367:Neoplasm Staging; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000532:radiotherapy*; D011879:Radiotherapy Dosage
chemical_list: D017430:Prostate-Specific Antigen