title: Prostate-specific antigen bounce after high-dose-rate prostate brachytherapy and hypofractionated external beam radiotherapy.
abstract: OBJECTIVE
  To report the frequency, timing, and magnitude of prostate-specific antigen (PSA) bounce (PB) in patients who received high-dose-rate (HDR) brachytherapy (HDRB) plus hypofractionated external beam radiation therapy (HypoRT) and to assess a possible correlation between PB and biochemical failure (BF).
  
  
  METHODS
  Patients with intermediate-risk prostate cancer received 10Gy single-fraction (192)Ir HDRB followed by 50Gy in 20 daily fractions of HypoRT without androgen deprivation therapy. All patients had a minimum 2-year followup. The PB was defined as PSA elevation higher than 0.2ng/mL from previous measurement with subsequent drop to pre-bounce level. The BF was defined as PSA nadir+2ng/mL.
  
  
  RESULTS
  A total of 114 patients treated between 2001 and 2009 were eligible for analysis. At a median followup of 66 months, the PB was found in 45 (39%) patients with a median time to bounce of 16 months (range, 3-76 months). The median time to PSA normalization after a PB was 9 months (range, 2-40 months). The median magnitude of PB was 0.45ng/mL (range, 0.2-6.62). The BF occurred in 12 (10.5%) patients of whom three had a PB. Median time to BF was 52.5 months. Four patients (3.5%) in the PB group fit the criteria for BF.
  
  
  CONCLUSIONS
  The PB is common after HDRB and HypoRT and can occur up to 76 months after treatment. It can rarely fit the criteria for BF. The time to PB is shorter than the time to BF. There is a lower incidence of BF in patients with a PB. An acknowledgment of this phenomenon should be made when interpreting PSA results during followup to prevent unnecessary interventions.
authors.affiliation: Division of Radiation Oncology, Department of Oncology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Nita
authors.initials: N
authors.lastname: Patel
authors.affiliation: Division of Radiation Oncology, Department of Oncology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Luis
authors.initials: L
authors.lastname: Souhami
authors.affiliation: Department of Urologic Oncology Research, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Jose João
authors.initials: JJ
authors.lastname: Mansure
authors.affiliation: Division of Radiation Oncology, Department of Oncology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Marie
authors.initials: M
authors.lastname: Duclos
authors.affiliation: Division of Urology, Department of Surgery, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Armen
authors.initials: A
authors.lastname: Aprikian
authors.affiliation: Division of Radiation Oncology, Department of Oncology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Sergio
authors.initials: S
authors.lastname: Faria
authors.affiliation: Division of Radiation Oncology, Department of Oncology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Marc
authors.initials: M
authors.lastname: David
authors.affiliation: Division of Radiation Oncology, Department of Oncology, McGill University Health Centre, Montreal, Quebec, Canada. Electronic address: fabio.cury@muhc.mcgill.ca.
authors.forename: Fabio L
authors.initials: FL
authors.lastname: Cury
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000532:radiotherapy*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood*; D001918:Brachytherapy / Q000379:methods*; D019583:Dose Fractionation, Radiation; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000532:radiotherapy*; D012189:Retrospective Studies; D017211:Treatment Failure
chemical_list: D014408:Biomarkers, Tumor; D017430:Prostate-Specific Antigen
keywords: Biochemical failure; HDR brachytherapy; Intermediate risk; PSA bounce; Prostate cancer