Current status and perspectives of brachytherapy for prostate cancer.

Permanent implant brachytherapy (PIB) for prostate cancer in a modern style was introduced in the 1980s. With the excellent outcome, the method prevailed rapidly in the United States in the 1990s, and it has become a standard treatment option at least for low-risk prostate cancer today. In Japan, PIB using (125)I free seeds was started in 2003, and it is being rapidly accepted. About 90 institutions in Japan have already started PIB, and about 10 000 patients have received this treatment during these 5 years. The outcome data for Japanese men should be established, and the efficacy of the combined use of external beam radiation therapy (EBRT) and hormone therapy should be examined. High-dose-rate (HDR) brachytherapy, which has many advantages over PIB, was started in the 1980s, firstly as a boost combined with EBRT, in Europe and the United States. In Japan, combined HDR brachytherapy and EBRT therapy was started in 1994. As for monotherapeutic HDR brachytherapy, the first series in the world was initiated in Osaka, Japan, in 1995. HDR brachytherapy, both as monotherapy and as combined therapy with EBRT, is yielding promising outcomes, and the study of these modalities should be continued. Mutual understanding and cooperation among urologists, radiation oncologists, and medical physicists is essential to enhance brachytherapy for prostate cancer.