[Radiotherapy: a significant treatment option in management of prostatic cancer]

In the management of patients with localized prostate cancer, both radical prostatectomy and radiotherapy are shown in the U.S. to be equally effective to control a local disease but associate with different types of toxicity. Therefore, both treatments are recommended for patients to choose freely. Recently, mainly in western countries, radiotherapy has achieved technological innovation so as to increase target tumor doses and to decrease the volume and dose of peritumoral normal tissues, by which the treatment outcome is further improved. Major innovative techniques include three-dimensional conformal radiotherapy (3D CRT) and a high dose-rate (HDR) brachytherapy system. Three-D CRT focuses radiation on the tumor through multiple portals minutely tailored to the tumor volume determined by computed tomography, in conjunction with a sophisticated treatment planning system. A HDR brachytherapy system provides high-tech interstitial radiotherapy; a remote afterloading system precludes radiation exposure of hospital workers and a computer-controlled source-scanning system enables optimization of dose distribution. In order to provide a variety of effective treatment options for Japanese patients, radiation oncologists must master these techniques in practice, in cooperation with urologists.