Trends in risk classification and primary therapy of Japanese patients with prostate cancer in Nara urological research and treatment group (NURTG) – comparison between 2004–2006, 2007–2009, and 2010–2012

BACKGROUND: To assess the trends in risk classification and primary therapy of Japanese prostate cancer patients who were diagnosed between 2004 and 2012. METHODS: A total of 7768 patients who were newly diagnosed with prostate cancer at Nara Medical University and its 23 affiliated hospitals between 2004 and 2012 were enrolled. The trends in risk classification and primary therapy in 2004–2006 (prior period), 2007–2009 (middle period), and 2010–2012 (latter period) were compared. RESULTS: The proportion of high-risk and worse patients significantly decreased in the latter period compared to the prior period (p < 0.001), while that of intermediate-risk patients significantly increased over the years (p < 0.001). The proportion of primary androgen deprivation therapy (PADT) was 50% in the prior period, 40% in the middle period, and 30% in the latter period, respectively. The proportions of radiation therapy and active surveillance significantly increased. The proportion of radical prostatectomy remained similar over these periods (30%). The primary therapy was significantly different between the three periods (p < 0.001). CONCLUSIONS: High-risk patients significantly decreased in the latter period. The use of PADT also significantly decreased, while radiation therapy and active surveillance significantly increased over these periods.