Childhood cancer in Japan: focusing on trend in mortality from 1970 to 2006.

OBJECTIVE This paper describes the mortality rates and trends from childhood cancer at the population level over a 37-year period in Japan and other developed countries. MATERIALS AND METHODS Age-standardized mortality rates were calculated by the direct method using age-specific mortality rates at 5-year age intervals and weights based on the age distribution of the standard world population. The joinpoint regression model was used to describe changes in trends. RESULTS For all cancers combined, the mortality rate during 2000-2006 was 2.20 per 100,000 population for boys and 1.89 for girls. Mortality for all cancers combined decreased since 1970s in Japan. A stable trend was observed in recent 5 years for girls. For leukemia, a declining trend was observed in the whole period for girls and in 1976-2006 for boys. Mortality rates for childhood central nervous system tumors have remained stable at a low level during 1980-2006. CONCLUSIONS The present study provides updated figures and trends in childhood cancer mortality in Japan and other developed countries. This will help to estimate care needs and to plan intervention and the quantity of appropriate childhood cancer treatment.