title: Hypofractionated helical tomotherapy using 2.5-2.6 Gy daily fractions for localized prostate cancer.
abstract: BACKGROUND
  The purpose of this study is to evaluate the tolerability of hypofractionated helical tomotherapy (HT) in the treatment of localized prostate cancer.
  
  
  METHODS
  We evaluated 48 patients with primary adenocarcinoma of the prostate (cT1-T3N0M0) who were treated with hypofractionated HT from August 2008 through July 2011. Hypofractionated regimens included: 68.04 Gy at 2.52 Gy/fraction, 70 Gy at 2.5 Gy/fraction, and 70.2 Gy at 2.6 Gy/fraction. Genitourinary (GU) and gastrointestinal (GI) toxicity was scored using the Radiation Therapy Oncology Group scoring system.
  
  
  RESULTS
  Thirty-two patients were treated with 68.04 Gy, 5 patients with 70 Gy, and 11 with 70.2 Gy. The median age at diagnosis was 69 years (range 49-87) and the median follow-up 11 months (range 7-40). Grade 2 acute GI toxicity occurred in 9 patients (19 %). No grade 3 or higher acute GI toxicity was observed. Grade 2 and 3 acute GU toxicities occurred in 19 and 6 % of patients, respectively. The incidence of late grade 2 GI and GU toxicity was 4 and 2 %, respectively. No grade 3 or higher late toxicities were observed. Multivariate analysis showed that patients treated at 2.6 Gy/fraction or those who received a total radiation dose ≥70 Gy had higher rates of grade ≥2 acute GU toxicity (P = 0.004 and P = 0.048, respectively).
  
  
  CONCLUSIONS
  Hypofractionated HT in the treatment of localized prostate cancer is well tolerated with no grade 3 or higher early or late GI and GU toxicities. Further research is needed to assess definitive late toxicity and tumor control.
authors.affiliation: Department of Radiation Oncology, Instituto Madrileño de Oncología/Grupo IMO, Clinica La Milagrosa, Calle Modesto Lafuente, 14, 28010 Madrid, Spain. chanodetriana@yahoo.es
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Lopez Guerra
authors.forename: Nicolas
authors.initials: N
authors.lastname: Isa
authors.forename: Raul
authors.initials: R
authors.lastname: Matute
authors.forename: Moises
authors.initials: M
authors.lastname: Russo
authors.forename: Fernando
authors.initials: F
authors.lastname: Puebla
authors.forename: Michelle Miran
authors.initials: MM
authors.lastname: Kim
authors.forename: Alberto
authors.initials: A
authors.lastname: Sanchez-Reyes
authors.forename: Cesar
authors.initials: C
authors.lastname: Beltran
authors.forename: Javier
authors.initials: J
authors.lastname: Jaen
authors.forename: Celine
authors.initials: C
authors.lastname: Bourgier
authors.forename: Hugo
authors.initials: H
authors.lastname: Marsiglia
mesh_terms: D000230:Adenocarcinoma / Q000453:epidemiology / Q000473:pathology / Q000532:radiotherapy*; D000368:Aged; D000369:Aged, 80 and over; D019583:Dose Fractionation, Radiation; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D058958:Organs at Risk / Q000528:radiation effects; D011471:Prostatic Neoplasms / Q000453:epidemiology / Q000473:pathology / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000453:epidemiology; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods*; D012189:Retrospective Studies