title: Single-fraction high-dose-rate brachytherapy and hypofractionated external beam radiation therapy in the treatment of intermediate-risk prostate cancer - long term results.
abstract: OBJECTIVE
  We present the long-term results of a cohort of patients with intermediate-risk prostate cancer (PC) treated with single-fraction high-dose-rate brachytherapy (HDRB) combined with hypofractionated external beam radiation therapy (HypoRT).
  
  
  METHODS
  Patients were treated exclusively with HDRB and HypoRT. HDRB delivered a dose of 10 Gy to the prostate surface and HypoRT consisted of 50 Gy delivered in 20 daily fractions. The first 121 consecutive patients with a minimum of 2 years posttreatment follow-up were assessed for toxicity and disease control.
  
  
  RESULTS
  The median follow-up was 65.2 months. No acute Grade III or higher toxicity was seen. Late Grade II gastrointestinal toxicity was seen in 9 patients (7.4%) and Grade III in 2 (1.6%). Late Grade III genitourinary toxicity was seen in 2 patients (1.6%). After a 24-month follow-up, a rebiopsy was offered to the first 58 consecutively treated patients, and 44 patients agreed with the procedure. Negative biopsies were found in 40 patients (91%). The 5-year biochemical relapse-free survival rate was 90.7% (95% CI, 84.5-96.9%), with 13 patients presenting biochemical failure. Among them, 9 were diagnosed with distant metastasis. Prostate cancer-specific and overall survival rates at 5 years were 100% and 98.8% (95% CI, 96.4-100%), respectively.
  
  
  CONCLUSIONS
  The combination of HDRB and HypoRT is well tolerated, with acceptable toxicity rates. Furthermore, results from rebiopsies revealed an encouraging rate of local control. These results confirm that the use of conformal RT techniques, adapted to specific biological tumor characteristics, have the potential to improve the therapeutic ratio in intermediate-risk PC patients.
authors.affiliation: Department of Radiation Oncology, McGill University Health Centre, Montreal, QC, Canada. fabio.cury@muhc.mcgill.ca
authors.forename: Fabio L
authors.initials: FL
authors.lastname: Cury
authors.forename: Marie
authors.initials: M
authors.lastname: Duclos
authors.forename: Armen
authors.initials: A
authors.lastname: Aprikian
authors.forename: Horacio
authors.initials: H
authors.lastname: Patrocinio
authors.forename: Wassim
authors.initials: W
authors.lastname: Kassouf
authors.forename: George
authors.initials: G
authors.lastname: Shenouda
authors.forename: Sergio
authors.initials: S
authors.lastname: Faria
authors.forename: Marc
authors.initials: M
authors.lastname: David
authors.forename: Luis
authors.initials: L
authors.lastname: Souhami
mesh_terms: D000368:Aged; D001706:Biopsy; D001918:Brachytherapy / Q000009:adverse effects / Q000379:methods*; D018572:Disease-Free Survival; D019583:Dose Fractionation, Radiation; D005500:Follow-Up Studies; D041981:Gastrointestinal Tract / Q000528:radiation effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D011467:Prostate / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000473:pathology; D012306:Risk; D014566:Urogenital System / Q000528:radiation effects
chemical_list: D017430:Prostate-Specific Antigen