[Clinical research on prostate cancer detected in Tone central hospital--comparison of survival rates between patients diagnosed with prostate cancer in and outside screening system].

OBJECTIVES: We investigated a clinical features and outcomes of prostate cancer detected in Tone Central Hospital. MATERIALS AND METHODS: We investigated clinical features of 532 patients with pathologically confirmed prostate cancer detected in our hospital between 1987 and 2006. Furthermore, we compared survival rates of screen detected prostate cancer (SC group) with those of non-screen detected prostate cancer (NSC group) for 362 cases diagnosed with prostate cancer after 1999. 362 cases consist of 223 patients in SC group and 139 patients in NSC group. RESULTS: Since 1987, the annual number of newly diagnosed patients has gradually increased and we recognized stage migration, a tendency toward an annual decrease in the incidence of stages A and D and an increase in that of stage B. The stage distributions of SC group (223 cases) and NSC group (139 cases), respectively, were 0.4% (1/223) and 9.4% (13/139) in stage A (p = 0.0011), 71.3% (159/223) and 31.7% (44/139) in stage B (p < 0.0001), 24.2% (54/223) and 23.7% (33/139) in stage C (p = 0.9182), and 4.0% (9/223) and 34.6% (46/223) in stage D (p < 0.0001). The 3, 5 and 7-year overall survival rates, respectively, were 95.6%, 92.7% and 84.1% in SC group, and 83.2%, 74.3% and 60.8% in NSC group (p < 0.0001). Furthermore, the 3, 5 and 7-year cause-specific survival rates, respectively, were 98.8%, 97.3% and 95.9% in SC group, and 90.2%, 87.7% and 79.4% in NSC group (p < 0.0001). CONCLUSIONS: Clinical stage distribution has been changed between 1987 and 2006. Furthermore, overall and cause specific survival rates were better in screen detected prostate cancer than non-screen detected prostate cancer, because of increases in earlier stage of prostate cancer in SC group.