title: Image-guided radiation therapy based on helical tomotherapy in prostate cancer: minimizing toxicity.
abstract: BACKGROUND
  We report the clinical results and prognostic factors of image-guided radiation therapy (RT) with helical tomotherapy (HT) for localized and recurrent prostate cancer (PC).
  
  
  METHODS
  We evaluated 70 patients with PC (primary diagnosis, n = 48; adjuvant, n = 5; salvage, n = 17) treated with HT from May 2006 through January 2011. The dose prescribed to the prostate/surgical bed ranged between 60 and 78 Gy. Potential risk factors for genitourinary (GU) and gastrointestinal (GI) toxicity were assessed.
  
  
  RESULTS
  The median age was 68 years (range 51-87 years). The median follow-up was 37 months (range 3-74 months). The rates of acute grade 2 GI and GU toxicities were 10 and 13%, respectively. Only 1 patient experienced acute grade 3 GU toxicity. The rates of late grade ≥ 2 GI and GU toxicities were 1% each. Multivariate analysis showed an association between rectum mean dose > median (39 Gy) and bladder median dose > median (46 Gy) with a higher grade of acute GI (p = 0.017) and GU (p = 0.019) toxicity, respectively. Additionally, older age was associated with late GU toxicity (p = 0.026).
  
  
  CONCLUSIONS
  Toxicity with HT is low and is associated with higher median/mean doses in organs at risk as well as with older age. A prospective validation would be necessary to confirm these results.
authors.affiliation: Máster en Aplicaciones tecnológicas avanzadas en Oncología Radioterápica, Universidad de Murcia y Fundación Grupo IMO, Madrid, Spain.
authors.forename: Catalina M
authors.initials: CM
authors.lastname: Acevedo-Henao
authors.forename: Jose L
authors.initials: JL
authors.lastname: Lopez Guerra
authors.forename: Raul
authors.initials: R
authors.lastname: Matute
authors.forename: Fernando
authors.initials: F
authors.lastname: Puebla
authors.forename: Moises
authors.initials: M
authors.lastname: Russo
authors.forename: Eleonor
authors.initials: E
authors.lastname: Rivin
authors.forename: Alberto
authors.initials: A
authors.lastname: Sanchez-Reyes
authors.forename: M José
authors.initials: MJ
authors.lastname: Ortiz
authors.forename: Ignacio
authors.initials: I
authors.lastname: Azinovic
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005767:Gastrointestinal Diseases / Q000209:etiology* / Q000517:prevention & control; D006801:Humans; D008297:Male; D052801:Male Urogenital Diseases / Q000209:etiology* / Q000517:prevention & control; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000209:etiology* / Q000517:prevention & control; D011835:Radiation Protection / Q000379:methods; D011879:Radiotherapy Dosage; D061089:Radiotherapy, Image-Guided / Q000009:adverse effects / Q000379:methods*; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects* / Q000379:methods*; D012189:Retrospective Studies; D036542:Tomography, Spiral Computed / Q000379:methods; D016896:Treatment Outcome