Evaluation of the efficacy of mass screening for uterine cancer in Japan.

To evaluate epidemiologically the efficacy of mass screening for uterine cancer, we compared the changes in the age-adjusted death rates from cancer of the uterus from 1969-1972 to 1973-1977 between the high coverage-rate areas and the control areas. The main results were: the decrease in the average age-adjusted death rate from cancer of the uterus was greater in the overall high coverage-rate (20% and over) areas (33.4%) than in the control areas (26.9%), but this difference was not statistically significant, when the high coverage-rate areas were limited to those where the uterine cancer death rate in 1969-1972 was greater than 90% of the average rate of all Japan, the decrease in the average age-adjusted death rate from cancer of the uterus was also greater in these high coverage-rate areas (68.1%) than in the control areas (44.2%) and this difference was statistically significant (P less than 0.01), when the high coverage-rate areas were limited to municipalities with a population size larger than 5,000, similar trends were observed. These results suggested that if mass screening for uterine cancer is widely conducted in areas with relatively high mortality rate from uterine cancer, it may be possible to reduce the mortality from this cancer at the community level.