title: Biochemical and clinical experience with real-time intraoperatively planned permanent prostate brachytherapy.
abstract: OBJECTIVE
  To evaluate patient characteristics and dosimetric parameters that predict biochemical failure (BCF) after real-time planned low-dose-rate prostate brachytherapy.
  
  
  METHODS
  From 1998 to 2008, a low-risk cohort by National Comprehensive Cancer Network criteria of 341 men with a median followup of 41.6 months was analyzed. This cohort had a median age of 65.1 years, prostate volume of 35.8cc, and pretreatment prostate-specific antigen of 5.6ng/mL. Patients had predominately Gleason 6 (95.9%) and T1c (81.3%) disease. About 3.6% of the patients received androgen deprivation therapy. Kaplan-Meier and Cox proportional hazards survival analysis methods were used to analyze predictors of BCF (Phoenix definition).
  
  
  RESULTS
  At 72 months, freedom from BCF was 91.1% (95% confidence interval=85.0-94.8). The median D(90) was 145.9Gy, and the median V(100) was 90.3%. Because of infrequent BCF, the following prostate volume groups were examined: 15-<25, 25-<35, 35-<45, and 45+cc. Of all possible predictors, only small prostate volume (15-<25cc group) was significantly associated with BCF (hazard ratio=8.44, 95% confidence interval=1.82-39.14, p=0.007). Using Kaplan-Meier analysis, time to BCF was also significantly increased in the lowest prostate volume 15-<25cc group with 24.1% failing at 48 months compared with 1.6-5.1% among the other groups.
  
  
  CONCLUSIONS
  Real-time planned low-dose-rate prostate brachytherapy provides excellent biochemical control as a single-agent treatment for low-risk prostate cancer with 91.1% freedom from BCF at 72 months. Only prostate volume less than 25cc was an independent predictor of BCF.
authors: Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
authors: Wilhelm
authors: W
authors: Lubbe
authors: Randi
authors: R
authors: Cohen
authors: Navesh
authors: N
authors: Sharma
authors: Karen
authors: K
authors: Ruth
authors: Ruth
authors: R
authors: Peters
authors: Jinsheng
authors: J
authors: Li
authors: Mark
authors: M
authors: Buyyounouski
authors: Alexander
authors: A
authors: Kutikov
authors: David
authors: D
authors: Chen
authors: Robert
authors: R
authors: Uzzo
authors: Eric
authors: E
authors: Horwitz
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000379:methods*; D015331:Cohort Studies; D018572:Disease-Free Survival; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011829:Radiation Dosage; D012307:Risk Factors
chemical_list: D007457:Iodine Radioisotopes; D017430:Prostate-Specific Antigen