[Future prediction of cancer deaths in Japan]

The number of cancer deaths and age-adjusted cancer death rates up to 2000 in Japan were predicted based on cancer death rates in 1972-1986. A simple linear regression model (y = a + bt, where t is calendar year and y is cancer death rate per 100,000 population) was fitted to the sex-age specific cancer mortality rates from 1972 to 1986 and cancer death rates in 1990, 1995 and 2000 were predicted by extrapolation method. The number of future cancer deaths was estimated after taking into account future population in Japan. The age-adjusted cancer rates up to 2000 were also estimated. The present study revealed that the numbers of deaths from stomach cancer (both sexes), uterine cancer and esophageal cancer (females) would keep declining, while all other cancers would increase in the future. The total number of cancer deaths in 2000 was estimated to be about 310,000 which is 1.62 times that of the total cancer deaths in 1986 (191,654). It was estimated that in 2000, lung cancer would rank top accounting for 22.2% of all cancer deaths, followed by cancers of the large intestine, liver, stomach, pancreas, biliary tract, leukemic, lymphoma and breast.