[Characteristics of uterine cancer detected by mass screening]

In Miyagi Prefecture, mass screening for cervical cancer was initiated in 1961. We organized the project in cooperation with the Miyagi Cancer Society. Because cases detected in mass screening were treated earlier, their prognoses were better than cases diagnosed in outpatient clinics. A high proportion of patients detected in stage 0 and I showed improved prognoses. In 1983, the central government established the first Health and Medical Services Law for the Aged to support the project. The standardized death rate of cervical cancer in Miyagi Prefecture fell from 12.1 per 100,000 in 1961 to 4.0 per 100,000 in 1994. A case-control study revealed that women who were screened, compared with women who had no prior screening, had an odds ratio for invasive cervical cancer of 0.14. The time interval of following the last negative smear was assessed, and we found that an odds ratio for a one-year interval was 0.09. However, there still remain problems, such as the lack of a further increase in the screening rate, fixation of examinees, and increase in the incidence of young women. Uterine body cancer is one of the increasing malignancies in Japan, as well as worldwide. Its epidemiological characteristics are as follows; 1) over 50 years old, 2) infertile and irregular menstruation, 3) post-menopause, and 4) atypical genital bleeding. Screening for uterine body cancer was started in 1987 under the second Health and Medical Services Law for the Aged. The target of the screening is limited to cases with the high-risk factors above described. We reported the results of mass screening in Miyagi Prefecture, elucidated the characteristics of uterine cancer detected by mass screening, and indicated the problems.