Effects of mass screening on age-specific incidence of neuroblastoma.

Using data from the Japan Children's Cancer Registry, we estimated the age-specific incidence rates of neuroblastoma. Before the neuroblastoma screening program started in 1985, the age-standardized incidence rates of neuroblastoma ranged from 7.5 to 9.1 x 10(-6) for children under 15 years of age. After the introduction of the screening program, the annual incidence rate rose to 19.5 x 10(-6). The annual incidence rate for neuroblastoma in children under 1 year of age was 150.60 x 10(-6) in the years 1989 to 1992, whereas the incidence rates only varied between 23.6 and 34.13 x 10(-6) in the 3 preceding 5-year periods. This increase in incidence for infants was accompanied by a minor decrease in incidence for children 2 to 3 years of age. However, this decrease may only partly explain the large increase in incidence for infants. Therefore, we suggest that screening may result in the detection of otherwise spontaneously regressing tumors. It is urgent to determine the contribution of screening to decreasing mortality before deciding whether this screening program should be continued.