title: Treatment outcome of high-dose image-guided intensity-modulated radiotherapy using intra-prostate fiducial markers for localized prostate cancer at a single institute in Japan.
abstract: BACKGROUND
  Several studies have confirmed the advantages of delivering high doses of external beam radiotherapy to achieve optimal tumor-control outcomes in patients with localized prostate cancer. We evaluated the medium-term treatment outcome after high-dose, image-guided intensity-modulated radiotherapy (IMRT) using intra-prostate fiducial markers for clinically localized prostate cancer.
  
  
  METHODS
  In total, 141 patients with localized prostate cancer treated with image-guided IMRT (76 Gy in 13 patients and 80 Gy in 128 patients) between 2003 and 2008 were enrolled in this study. The patients were classified according to the National Comprehensive Cancer Network-defined risk groups. Thirty-six intermediate-risk patients and 105 high-risk patients were included. Androgen-deprivation therapy was performed in 124 patients (88%) for a median of 11 months (range: 2-88 months). Prostate-specific antigen (PSA) relapse was defined according to the Phoenix-definition (i.e., an absolute nadir plus 2 ng/ml dated at the call). The 5-year actuarial PSA relapse-free survival, the 5-year distant metastasis-free survival, the 5-year cause-specific survival (CSS), the 5-year overall survival (OS) outcomes and the acute and late toxicities were analyzed. The toxicity data were scored according to the Common Terminology Criteria for Adverse Events, version 4.0. The median follow-up was 60 months.
  
  
  RESULTS
  The 5-year PSA relapse-free survival rates were 100% for the intermediate-risk patients and 82.2% for the high-risk patients; the 5-year actuarial distant metastasis-free survival rates were 100% and 95% for the intermediate- and high-risk patients, respectively; the 5-year CSS rates were 100% for both patient subsets; and the 5-year OS rates were 100% and 91.7% for the intermediate- and high-risk patients, respectively. The Gleason score (<8 vs. ≥ 8) was significant for the 5-year PSA relapse-free survival on multivariate analysis (p = 0.044). There was no grade 3 or 4 acute toxicity. The incidence of grade 2 acute gastrointestinal (GI) and genitourinary (GU) toxicities were 1.4% and 8.5%, respectively. The 5-year actuarial likelihood of late grade 2-3 GI and GU toxicities were 6% and 6.3%, respectively. No grade 4 GI or GU late toxicity was observed.
  
  
  CONCLUSIONS
  These medium-term results demonstrate a good tolerance of high-dose image-guided IMRT. However, further follow-up is needed to confirm the long-term treatment outcomes.
authors: Department of Radiological Technology, School of Health Sciences, Faculty of medicine, Tohoku University, Sendai, Japan. ktakeda-rad@umin.net
authors: Ken
authors: K
authors: Takeda
authors: Yoshihiro
authors: Y
authors: Takai
authors: Kakutaro
authors: K
authors: Narazaki
authors: Masatoshi
authors: M
authors: Mitsuya
authors: Rei
authors: R
authors: Umezawa
authors: Noriyuki
authors: N
authors: Kadoya
authors: Yukio
authors: Y
authors: Fujita
authors: Toshiyuki
authors: T
authors: Sugawara
authors: Masaki
authors: M
authors: Kubozono
authors: Eiji
authors: E
authors: Shimizu
authors: Keiko
authors: K
authors: Abe
authors: Yuko
authors: Y
authors: Shirata
authors: Yohjiro
authors: Y
authors: Ishikawa
authors: Takaya
authors: T
authors: Yamamoto
authors: Maiko
authors: M
authors: Kozumi
authors: Suguru
authors: S
authors: Dobashi
authors: Haruo
authors: H
authors: Matsushita
authors: Koichi
authors: K
authors: Chida
authors: Shigeto
authors: S
authors: Ishidoya
authors: Yoichi
authors: Y
authors: Arai
authors: Keiichi
authors: K
authors: Jingu
authors: Shogo
authors: S
authors: Yamada
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D057918:Fiducial Markers; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011878:Radiotherapy / Q000379:methods*; D061089:Radiotherapy, Image-Guided / Q000379:methods*; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D012008:Recurrence; D012189:Retrospective Studies; D012306:Risk; D016896:Treatment Outcome