title: Prospective Phase II Trial of Once-weekly Hypofractionated Radiation Therapy for Low-risk Adenocarcinoma of the Prostate: Late Toxicities and Outcomes.
abstract: To report the long-term toxicities and sexual quality of life of a once-weekly hypofractionated radiation therapy schedule for low-risk prostate cancer.
  
  
  
  A multi-institutional phase II trial was conducted, using a three-dimensional conformal radiation therapy (3D-CRT) approach for low-risk prostate cancer (T1a-T2a, Gleason ≤ 6 and prostate-specific antigen ≤ 10 ng/ml). Forty-five Gray (Gy) were delivered in nine fractions of 5 Gy given on a weekly basis. Acute and late genitourinary and gastrointestinal toxicities were graded according to the Radiation Therapy Oncology Group toxicity scale. Sexual function and sexual bother were assessed with the Expanded Prostate Cancer Index Composite (EPIC) questionnaire.
  
  
  
  Between March 2006 and August 2008, 80 patients were treated, with a median age of 69 years (interquartile range 64-72). The median follow-up was 83 months (interquartile range 73-85 months). At 7 years, overall survival was 88%. No patients died of prostate cancer. Cumulative grade ≥2 genitourinary and gastrointestinal late toxicity was reported for 31.3% and 30% of our patients, respectively. Cumulative grade ≥3 genitourinary and gastrointestinal late toxicity was seen in 3.8% and 12.5% of cases, respectively. Late genitourinary grade 2 toxicity was correlated with the occurrence of acute genitourinary grade 2 toxicity (P = 0.006). The occurrence of late gastrointestinal toxicity was not correlated with acute gastrointestinal toxicity. Pre-treatment EPIC sexual function was low (37.5%) and the mean EPIC sexual function score at 7 years after treatment was 14%. On the other hand, pre-treatment EPIC sexual bother reached 80.5%, meaning little bother, and remained stable during follow-up.
  
  
  
  Once-weekly 3D-CRT leads to excellent biochemical disease-free survival and acceptable toxicities. Pre-treatment EPIC sexual function dropped by 42% at 5 years of follow-up. This functional deficit did not bother patients, possibly due to the already low sexual function at baseline.
authors.affiliation: Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal (CHUM) - Hôpital Notre-Dame, Montreal, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Zimmermann
authors.affiliation: Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal (CHUM) - Hôpital Notre-Dame, Montreal, Canada. Electronic address: daniel.taussky.chum@ssss.gouv.qc.ca.
authors.forename: D
authors.initials: D
authors.lastname: Taussky
authors.affiliation: Department of Radiation Oncology, Hôpital Maisonneuve-Rosemont (HMR), Montreal, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Menkarios
authors.affiliation: Department of Radiation Oncology, Centre Hospitalier Universitaire de Québec (CHUQ), Quebec City, Canada.
authors.forename: É
authors.initials: É
authors.lastname: Vigneault
authors.affiliation: Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal (CHUM) - Hôpital Notre-Dame, Montreal, Canada.
authors.forename: M-C
authors.initials: MC
authors.lastname: Beauchemin
authors.affiliation: Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal (CHUM) - Hôpital Notre-Dame, Montreal, Canada.
authors.forename: J-P
authors.initials: JP
authors.lastname: Bahary
authors.affiliation: Department of Radiation Oncology, Centre Hospitalier Universitaire de Québec (CHUQ), Quebec City, Canada.
authors.forename: A-A-G
authors.initials: AA
authors.lastname: Martin
authors.affiliation: Department of Radiation Oncology, Centre Hospitalier Universitaire de Québec (CHUQ), Quebec City, Canada.
authors.forename: L-V
authors.initials: LV
authors.lastname: Diaz de Bedoya
authors.affiliation: Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal (CHUM) - Hôpital Notre-Dame, Montreal, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Lambert
mesh_terms: D000230:Adenocarcinoma / Q000532:radiotherapy*; D000368:Aged; D005767:Gastrointestinal Diseases / Q000209:etiology*; D006801:Humans; D008297:Male; D052801:Male Urogenital Diseases / Q000209:etiology*; D008875:Middle Aged; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011788:Quality of Life; D000069473:Radiation Dose Hypofractionation; D011832:Radiation Injuries / Q000209:etiology*; D020266:Radiotherapy, Conformal / Q000009:adverse effects*; D012307:Risk Factors; D011795:Surveys and Questionnaires; D015996:Survival Rate; D016896:Treatment Outcome
keywords: Hypofractionation; prostate cancer; radiation therapy; sexual function