title: Radical external beam radiotherapy for prostate cancer in Japan: results of the 1999-2001 patterns of care process survey.
abstract: BACKGROUND
  The Patterns of Care Study evaluated standards of practice for patients with clinically localized prostate cancer treated with radiotherapy in Japan. This study examined the influence of institutional stratification on care for patients receiving radical external beam radiotherapy.
  
  
  METHODS
  A national survey of 66 institutions was conducted using two-stage cluster sampling, and detailed information was accumulated on 283 patients who received radiotherapy between 1999 and 2001.
  
  
  RESULTS
  In A (academic) and B (non-academic) institutions, more than 80% of patients had intermediate or unfavorable risk disease. Although there were no significant differences in disease characteristics between A and B institutions, institutional stratification significantly affected radiotherapy practice patterns, such as the use of a CT-based treatment planning (A1: 91.5%, B: 77.1%; P = 0.0007) and the use of conformal therapy (A: 56.4%, B: 24.1%; P < 0.0001). CT-based treatment planning and conformal therapy significantly influenced total radiation dose (P < 0.0001 for each). Hormonal therapy was commonly used in both A and B institutions (A: 89.0%, B: 90.7%). Many patients with a favorable prognosis (A: 62.5%, B: 91.7%) received hormonal therapy, and most patients with unfavorable risk disease (A: 93.6%, B: 91.6%) also received hormonal therapy.
  
  
  CONCLUSIONS
  During the period 1999-2001, the majority of prostate cancer patients treated in Japan with radical external beam radiotherapy had advanced diseases. Institutional stratification significantly affected radiotherapy practice patterns, with the notable exception that radiotherapy was commonly combined with hormonal therapy regardless of the institutional stratification and individual risk.
authors.affiliation: Department of Radiology, University of the Ryukyus, Okinawa, Japan. kogawa@med.u-ryukyu.ac.jp
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Ogawa
authors.forename: Katsumasa
authors.initials: K
authors.lastname: Nakamura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Onishi
authors.forename: Tomonari
authors.initials: T
authors.lastname: Sasaki
authors.forename: Masahiko
authors.initials: M
authors.lastname: Koizumi
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Shioyama
authors.forename: Takafumi
authors.initials: T
authors.lastname: Komiyama
authors.forename: Yuuki
authors.initials: Y
authors.lastname: Miyabe
authors.forename: Teruki
authors.initials: T
authors.lastname: Teshima
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use; D003131:Combined Modality Therapy; D019538:Health Care Surveys; D006801:Humans; D007324:Institutional Management Teams / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D010818:Practice Patterns, Physicians'; D011471:Prostatic Neoplasms / Q000188:drug therapy / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000706:statistics & numerical data; D020266:Radiotherapy, Conformal / Q000706:statistics & numerical data; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D018931:Antineoplastic Agents, Hormonal