title: High-dose radiotherapy with helical tomotherapy and long-term androgen deprivation therapy for prostate cancer: 5-year outcomes.
abstract: OBJECTIVE
  We aimed to examine outcomes of high-dose radiotherapy with helical tomotherapy (HT) and long-term androgen deprivation therapy (ADT) for T1-4N0M0 prostate cancer.
  
  
  METHODS
  A total of 391 patients treated with HT between June 2006 and December 2013 were included in this retrospective study. All patients received neoadjuvant ADT for a median duration of 10 months followed by HT at a median dose of 78 Gy [interquartile range (IQR) 78-78]. The times of median adjuvant and total ADT were 19 and 27 months (IQR 20-31), respectively. The risk stratification followed the 2015 National Comprehensive Cancer Network criteria. Biochemical disease-free survival (bDFS) followed the Phoenix definition. Toxicity was scored according to the Radiation Therapy Oncology Group morbidity grading scale.
  
  
  RESULTS
  Median follow-up from HT start was 60 months (IQR 42-81). Five-year bDFS rates for low-, intermediate-, high-, and very-high-risk groups were 100, 98.2, 97.7, and 87.9 %, respectively. We observed clinical relapse in nine very-high-risk patients and one high-risk patient, resulting in a 5-year clinical relapse-free survival of 100, 100, 99.4, and 91.7 %, respectively, for each risk group. Three patients died of prostate cancer, resulting in a 5-year prostate cancer-specific survival of 99.6 %. The late grade 2 or higher gastrointestinal and genitourinary toxicities were 9.7 and 10.7 %. No cardiovascular fatal events were observed.
  
  
  CONCLUSIONS
  This report confirmed the excellent outcomes with acceptable late toxicities with the combination of HT and long-term ADT. Longer follow-up is crucial to further determine the treatment effect and toxicity.
authors.affiliation: Department of Radiation Oncology, Aichi Cancer Center Hospital, 1-1 Kanokoden, Chikusaku, Nagoya, 464-8681, Japan. ntomita@aichi-cc.jp.
authors.forename: Natsuo
authors.initials: N
authors.lastname: Tomita
authors.affiliation: Department of Urology, Aichi Cancer Center Hospital, Nagoya, Japan.
authors.forename: Norihito
authors.initials: N
authors.lastname: Soga
authors.affiliation: Department of Urology, Aichi Cancer Center Hospital, Nagoya, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ogura
authors.affiliation: Department of Urology, Aichi Cancer Center Hospital, Nagoya, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Hayashi
authors.affiliation: Department of Urology, Aichi Cancer Center Hospital, Nagoya, Japan.
authors.forename: Takumi
authors.initials: T
authors.lastname: Kageyama
authors.affiliation: Department of Radiation Oncology, Aichi Cancer Center Hospital, 1-1 Kanokoden, Chikusaku, Nagoya, 464-8681, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Ito
authors.affiliation: Department of Radiation Oncology, Aichi Cancer Center Hospital, 1-1 Kanokoden, Chikusaku, Nagoya, 464-8681, Japan.
authors.forename: Yutaro
authors.initials: Y
authors.lastname: Koide
authors.affiliation: Department of Radiation Oncology, Aichi Cancer Center Hospital, 1-1 Kanokoden, Chikusaku, Nagoya, 464-8681, Japan.
authors.forename: Maiko
authors.initials: M
authors.lastname: Yoshida
authors.affiliation: Department of Radiation Oncology, Aichi Cancer Center Hospital, 1-1 Kanokoden, Chikusaku, Nagoya, 464-8681, Japan.
authors.forename: Kana
authors.initials: K
authors.lastname: Kimura
authors.affiliation: Department of Radiation Oncology, Aichi Cancer Center Hospital, 1-1 Kanokoden, Chikusaku, Nagoya, 464-8681, Japan.
authors.forename: Chiyoko
authors.initials: C
authors.lastname: Makita
authors.affiliation: Department of Radiation Oncology, Aichi Cancer Center Hospital, 1-1 Kanokoden, Chikusaku, Nagoya, 464-8681, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tachibana
authors.affiliation: Department of Radiation Oncology, Aichi Cancer Center Hospital, 1-1 Kanokoden, Chikusaku, Nagoya, 464-8681, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kodaira
mesh_terms: D000368:Aged; D000726:Androgen Antagonists / Q000627:therapeutic use*; D059248:Chemoradiotherapy; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D008297:Male; D008875:Middle Aged; D016609:Neoplasms, Second Primary; D011471:Prostatic Neoplasms / Q000628:therapy*; D016896:Treatment Outcome
chemical_list: D000726:Androgen Antagonists
keywords: Androgen deprivation therapy; Helical tomotherapy; Image-guided radiation therapy; Intensity-modulated radiation therapy; Prostate cancer