title: Hypofractionated radiation therapy (66 Gy in 22 fractions at 3 Gy per fraction) for favorable-risk prostate cancer: long-term outcomes.
abstract: OBJECTIVE
  To report long-term outcomes of low- and intermediate-risk prostate cancer patients treated with high-dose hypofractionated radiation therapy (HypoRT).
  
  
  METHODS
  Patients with low- and intermediate-risk prostate cancer were treated using 3-dimensional conformal radiation therapy to a dose of 66 Gy in 22 daily fractions of 3 Gy without hormonal therapy. A uniform 7-mm margin was created around the prostate for the planning target volume, and treatment was prescribed to the isocenter. Treatment was delivered using daily ultrasound image-guided radiation therapy. Common Terminology Criteria for Adverse Events, version 3.0, was used to prospectively score toxicity. Biochemical failure was defined as the nadir prostate-specific antigen level plus 2 ng/mL.
  
  
  RESULTS
  A total of 129 patients were treated between November 2002 and December 2005. With a median follow-up of 90 months, the 5- and 8-year actuarial biochemical control rates were 97% and 92%, respectively. The 5- and 8-year actuarial overall survival rates were 92% and 88%, respectively. Only 1 patient died from prostate cancer at 92 months after treatment, giving an 8-year actuarial cancer-specific survival of 98%. Radiation therapy was well tolerated, with 57% of patients not experiencing any acute gastrointestinal (GI) or genitourinary (GU) toxicity. For late toxicity, the worst grade ≥2 rate for GI and GU toxicity was 27% and 33%, respectively. There was no grade >3 toxicity. At last follow-up, the rate of grade ≥2 for both GI and GU toxicity was only 1.5%.
  
  
  CONCLUSIONS
  Hypofractionation with 66 Gy in 22 fractions prescribed to the isocenter using 3-dimensional conformal radiation therapy produces excellent biochemical control rates, with moderate toxicity. However, this regimen cannot be extrapolated to the intensity modulated radiation therapy technique.
authors.affiliation: Department of Radiation Oncology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Nita
authors.initials: N
authors.lastname: Patel
authors.forename: Sergio
authors.initials: S
authors.lastname: Faria
authors.forename: Fabio
authors.initials: F
authors.lastname: Cury
authors.forename: Marc
authors.initials: M
authors.lastname: David
authors.forename: Marie
authors.initials: M
authors.lastname: Duclos
authors.forename: George
authors.initials: G
authors.lastname: Shenouda
authors.forename: Russell
authors.initials: R
authors.lastname: Ruo
authors.forename: Luis
authors.initials: L
authors.lastname: Souhami
mesh_terms: D000368:Aged; D019583:Dose Fractionation, Radiation; D041981:Gastrointestinal Tract / Q000528:radiation effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D020266:Radiotherapy, Conformal / Q000009:adverse effects / Q000379:methods*; D061089:Radiotherapy, Image-Guided / Q000379:methods*; D050397:Radiotherapy, Intensity-Modulated; D012306:Risk; D015996:Survival Rate; D018084:Ultrasonography, Interventional / Q000379:methods; D014566:Urogenital System / Q000528:radiation effects
chemical_list: D017430:Prostate-Specific Antigen