title: Late toxicity and five year outcomes after high-dose-rate brachytherapy as a monotherapy for localized prostate cancer.
abstract: BACKGROUND
  To determine the 5-year outcome after high-dose-rate brachytherapy (HDR-BT) as a monotherapy.
  
  
  METHODS
  Between 10/2003 and 06/2006, 36 patients with low (28) and intermediate (8) risk prostate cancer were treated by HDR-BT monotherapy. All patients received one implant and 4 fractions of 9.5 Gy within 48 hours for a total prescribed dose (PD) of 38 Gy. Five patients received concomitant androgen deprivation therapy (ADT). Toxicity was scored according to the common terminology criteria for adverse events from the National Cancer Institute (CTCAE) version 3.0. Biochemical recurrence was defined according to the Phoenix criteria and analyzed using the Kaplan Meier method. Predictors for late grade 3 GU toxicity were analyzed using univariate and multivariate Cox regression analyses.
  
  
  RESULTS
  The median follow-up was 6.9 years (range, 1.5-8.0 years). Late grade 2 and 3 genitourinary (GU) toxicity was observed in 10 (28%) and 7 (19%) patients, respectively. The actuarial proportion of patients with late grade 3 GU toxicity at 5 years was 17.7%. Late grade 2 and 3 gastrointestinal (GI) toxicities were not observed. The crude erectile function preservation rate in patients without ADT was 75%. The 5 year biochemical recurrence-free survival (bRFS) rate was 97%. Late grade 3 GU toxicity was associated with the urethral volume (p = 0.001) and the urethral V120 (urethral volume receiving ≥120% of the PD; p = 0.0005) after multivariate Cox regression.
  
  
  CONCLUSIONS
  After HDR-BT monotherapy late grade 3 GU was observed relatively frequently and was associated with the urethral V120. GI toxicity was negligible, the erectile function preservation rate and the bRFS rate was excellent.
authors.affiliation: Department of Radiation Oncology, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, Berlin 13353, Germany. pirus.ghadjar@charite.de.
authors.forename: Pirus
authors.initials: P
authors.lastname: Ghadjar
authors.forename: Sebastian L
authors.initials: SL
authors.lastname: Oesch
authors.forename: Cyrill A
authors.initials: CA
authors.lastname: Rentsch
authors.forename: Bernhard
authors.initials: B
authors.lastname: Isaak
authors.forename: Nikola
authors.initials: N
authors.lastname: Cihoric
authors.forename: Peter
authors.initials: P
authors.lastname: Manser
authors.forename: George N
authors.initials: GN
authors.lastname: Thalmann
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Aebersold
mesh_terms: D001918:Brachytherapy / Q000009:adverse effects*; D005500:Follow-Up Studies; D041981:Gastrointestinal Tract / Q000528:radiation effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology / Q000532:radiotherapy*; D009367:Neoplasm Staging; D011379:Prognosis; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000209:etiology* / Q000473:pathology; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D012189:Retrospective Studies; D014566:Urogenital System / Q000528:radiation effects*