Firm measures are required to effect any significant decrease in the Japanese age-adjusted mortality rate from malignant neoplasms for the 21st century.

The Japanese have the longest lifespan worldwide, but this has been mostly due to reductions in the mortality rates from diseases other than malignant neoplasms. Changes in the age-adjusted mortality rates (AMRs) for malignant neoplasms in Japan from 1950 to 2000 are analyzed to elucidate the overall trend. The overall AMRs for all malignant neoplasms in men increased from 1950 to 2000, and decreased slowly in women during the same period. Changes since 1990 have been small in both genders, but show a hopeful trend towards a decrease in the total AMR since 1995. These trends reflect a balance between the decreased AMR from gastric (both male and female) and uterine cancers and increases in many other malignant neoplasms. However, in the period 1990-2000, the decrease in the AMR from gastric and uterine cancers has shown a trend towards leveling off. Therefore, improving the trend towards reductions in cancer incidence and mortality in the 21st century and beyond will depend on achieving changes in other cancer sites, which can only be realized through the twofold approach of preventative medicine and research as well as improvements in the levels of diagnosis and therapy. Much more emphasis must therefore be placed on primary prevention, in particular on anti-smoking campaigns, as well as stepping-up research into the etiology of, and novel treatments for other malignant neoplasms, especially colorectal and breast cancers.