title: Patterns of practice in intensity-modulated radiation therapy and image-guided radiation therapy for prostate cancer in Japan.
abstract: BACKGROUND
  The purpose of this study was to compare the prevalence of treatment techniques including intensity-modulated radiation therapy and image-guided radiation therapy in external-beam radiation therapy for prostate cancer in Japan.
  
  
  METHODS
  A national survey on the current status of external-beam radiation therapy for prostate cancer was performed in 2010. We sent questionnaires to 139 major radiotherapy facilities in Japan, of which 115 (82.7%) were returned.
  
  
  RESULTS
  Intensity-modulated radiation therapy was conducted at 67 facilities (58.3%), while image-guided radiation therapy was conducted at 70 facilities (60.9%). Simulations and treatments were performed in the supine position at most facilities. In two-thirds of the facilities, a filling bladder was requested. Approximately 80% of the facilities inserted a tube or encouraged defecation when the rectum was dilated. Some kind of fixation method was used at 102 facilities (88.7%). Magnetic resonance imaging was routinely performed for treatment planning at 32 facilities (27.8%). The median total dose was 76 Gy with intensity-modulated radiation therapy and 70 Gy with three-dimensional radiation therapy. The doses were prescribed at the isocenter at the facilities that conducted three-dimensional radiation therapy. In contrast, the dose prescription varied at the facilities that conducted intensity-modulated radiation therapy. Of the 70 facilities that could perform image-guided radiation therapy, 33 (47.1%) conducted bone matching, 28 (40.0%) conducted prostate matching and 9 (12.9%) used metal markers. Prostate or metal marker matching tended to produce a smaller margin than bone matching.
  
  
  CONCLUSIONS
  The results of the survey identified current patterns in the treatment planning and delivery processes of external-beam radiation therapy for prostate cancer in Japan.
authors: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan. nakam@radiol.med.kyushu-u.ac.jp
authors: Katsumasa
authors: K
authors: Nakamura
authors: Tetsuo
authors: T
authors: Akimoto
authors: Takashi
authors: T
authors: Mizowaki
authors: Kazuo
authors: K
authors: Hatano
authors: Takeshi
authors: T
authors: Kodaira
authors: Naoki
authors: N
authors: Nakamura
authors: Takuyo
authors: T
authors: Kozuka
authors: Naoto
authors: N
authors: Shikama
authors: Yoshikazu
authors: Y
authors: Kagami
mesh_terms: D019583:Dose Fractionation, Radiation; D006801:Humans; D008297:Male; D011467:Prostate / Q000528:radiation effects; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011881:Radiotherapy, Computer-Assisted / Q000706:statistics & numerical data*; D050397:Radiotherapy, Intensity-Modulated / Q000706:statistics & numerical data*; D011795:Surveys and Questionnaires; D001743:Urinary Bladder / Q000528:radiation effects