Effectiveness of mass screening for the prognosis of prostate cancer patients in Japanese communities

Background. A study was conducted to investigate the effectiveness of mass screening (MS) for prostate cancer in Japanese communities using the long-term follow-up results. Methods. Subjects were 279 patients with prostate cancer detected by MS in Gunma prefecture (MS group) and 624 patients with prostate cancer who did not undergo screening (non-MS group). From the follow-up data, the prognoses were compared between the groups. Results. The ratio of patients with Stage II cancer was higher for the MS group (59.1%,) when compared to non-MS group (25.3%). As a whole, the prognosis of the MS group was more favorable than that of the non-MS group for relative survival rate. Prognosis was especially favorable for patients with Stage III prostate cancer in mass screening group C, considering the effect of lead-time bias. Conclusions. Early detection and longer survival of the patients with prostate cancer detected by mass screening suggested the effectiveness of prostate cancer screening. Prostate 50: 262-269, 2002. (C) 2002 Wiley-Liss, Inc.