[The mass screening for prostate cancer and the age eligibility. Gunma Urological Oncology Study Group].

Background: The age eligibility for the mass screening (MS) for prostate cancer was investigated.
Methods and Materials: This study was performed in subjects examined by MS from 1981 to 1994 in Gunma Prefecture, Japan. MS was performed by digital rectal examination (DRE) and prostatic acid phosphatase from 1981 to 1991, and by DRE, transrectal ultrasonography and prostate specific antigen from 1992 to 1994.
Results: It was demonstrated that the prostate cancer detection rate was affected by the ratio of subjects newly and previously examined, the age distribution in the group examined and the diagnostic modality. It was also demonstrated that the detection rate of early stage prostate cancer was also affected by the age distribution and the diagnostic modality. The effective detection rate was determined on the assumption that the purpose of MS is the detection of the subjects who have the indication for the radical prostatectomy, and the effective detection rate was calculated in the range from 50 to 69 years for age eligibility, and B and C for clinical stage. It was estimated that effective detection rate was 0.37 to 0.61%. They were higher than the detection rate of MS for other organ cancers.
Conclusion: The eligibility is 50 to 69 years. If subjects in the range of 70 to 74 are included in this project, it is necessary to make an effort practice a subject-education about the prostate cancer natural history and the radical prostatectomy indication.