Mizuki Onozawa1, Shiro Hinotsu2, Taiji Tsukamoto3, Mototsugu Oya4, Osamu Ogawa5, Tadaichi Kitamura6, Kazuhiro Suzuki7, Seiji Naito8, Mikio Namiki9, Kazuo Nishimura10, Yoshihiko Hirao11, Hideyuki Akaza12. 1. Department of Urology, Tokyo-Kita Medical Center, Tokyo onozawa-jua@umin.ac.jp. 2. Center for Innovative Clinical Medicine, Okayama University Hospital, Okayama. 3. Department of Urology, Sapporo Medical University School of Medicine, Sapporo. 4. Department of Urology, School of Medicine, Keio University, Tokyo. 5. Department of Urology, Kyoto University Graduate School of Medicine, Kyoto. 6. Department of Urology, Shinsui Clinic, Tokyo. 7. Department of Urology, Gunma University Graduate School of Medicine, Maebashi. 8. Department of Urology, Graduate School of Medical Sciences, Kyushu University, Fukuoka. 9. Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Kanazawa. 10. Department of Urology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka. 11. Osaka Gyoumeikan Hospital, Osaka. 12. Research Center for Advanced Science and Technology, University of Tokyo, Tokyo, Japan.
Abstract
OBJECTIVE: The objective of the present study was to investigate the trends over time in the initial treatment of prostate cancer in Japan. METHODS: A total of 8291 patients with newly diagnosed prostate cancer whose treatment started in 2010 were registered in a multi-institutional observational study undertaken nationwide across Japan by the Japan Prostate Cancer Study Group. Each patient's background characteristics and initial treatment were recorded. RESULTS: The median age at diagnosis was 71 years. The proportion of T1c disease was 40.5% and that of M1 disease was 10.4%. The prostate-specific antigen level was <10 ng/ml in 52.0% of the patients. High-, intermediate- and low-risk patients as determined by D'Amico's classification system made up 19.3, 29.8 and 25.9% of the cases, respectively. The initial treatment was androgen depletion therapy in 40.2%, radical prostatectomy in 32.0% (17.3% of these involved laparoscopic prostatectomy), radiation in 21.0% (46.4% of these involved brachytherapy). In cases of organ-confined disease, radical prostatectomy was selected in 39.5%, androgen depletion therapy in 28.0% and radiation in 23.9%. In D'Amico's low-risk group, the proportion treated with radiation was nearly equal to that treated with radical prostatectomy (30.2 and 32.7%, respectively); 73.2% of the radiation treatments involved brachytherapy. CONCLUSION: Compared with previous Japanese studies, radiation use was increased by ∼10%. This increased proportion of radiation use was a typical trend in initial therapy for newly diagnosed prostate cancer cases in Japan. Although androgen depletion therapy use was decreased, it was selected in a high proportion of the patients irrespective of the disease stage.
OBJECTIVE: The objective of the present study was to investigate the trends over time in the initial treatment of prostate cancer in Japan. METHODS: A total of 8291 patients with newly diagnosed prostate cancer whose treatment started in 2010 were registered in a multi-institutional observational study undertaken nationwide across Japan by the Japan Prostate Cancer Study Group. Each patient's background characteristics and initial treatment were recorded. RESULTS: The median age at diagnosis was 71 years. The proportion of T1c disease was 40.5% and that of M1 disease was 10.4%. The prostate-specific antigen level was <10 ng/ml in 52.0% of the patients. High-, intermediate- and low-risk patients as determined by D'Amico's classification system made up 19.3, 29.8 and 25.9% of the cases, respectively. The initial treatment was androgen depletion therapy in 40.2%, radical prostatectomy in 32.0% (17.3% of these involved laparoscopic prostatectomy), radiation in 21.0% (46.4% of these involved brachytherapy). In cases of organ-confined disease, radical prostatectomy was selected in 39.5%, androgen depletion therapy in 28.0% and radiation in 23.9%. In D'Amico's low-risk group, the proportion treated with radiation was nearly equal to that treated with radical prostatectomy (30.2 and 32.7%, respectively); 73.2% of the radiation treatments involved brachytherapy. CONCLUSION: Compared with previous Japanese studies, radiation use was increased by ∼10%. This increased proportion of radiation use was a typical trend in initial therapy for newly diagnosed prostate cancer cases in Japan. Although androgen depletion therapy use was decreased, it was selected in a high proportion of the patients irrespective of the disease stage.