Radical external beam radiotherapy for prostate cancer in Japan: results of the 1999-2001 patterns of care process survey.
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.
Ogawa
Kazuhiko
K
Department of Radiology, University of the Ryukyus, Okinawa, Japan. kogawa@med.u-ryukyu.ac.jp
Nakamura
Katsumasa
K
Onishi
Hiroshi
H
Sasaki
Tomonari
T
Koizumi
Masahiko
M
Shioyama
Yoshiyuki
Y
Komiyama
Takafumi
T
Miyabe
Yuuki
Y
Teshima
Teruki
T
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
D018931:Antineoplastic Agents, Hormonal