The incidence and mortality rates of neuroblastoma cases before and after the cessation of the mass screening program in Japan: A descriptive study.

Abstract

In 2003, Japan's Ministry of Health, Labour and Welfare halted the neuroblastoma (NB) mass screening program, running since 1985. This study aimed to examine whether NB incidence and mortality changed before and after the program halted. This is a descriptive population-based study. We used data from the Monitoring of Cancer Incidence in Japan (MCIJ) project, Vital Statistics of Japan, and Japanese CANcer Survival Information for Society (J-CANSIS). Incidence rate, cumulative incidence rate, mortality rate, cumulative mortality rate, and relative 5-year survival for NB were calculated. Children were divided into two birth cohort groups, consisting of children born before, or after the cessation of the NB mass screening program. We compared the two cohorts, with regards to the cumulative incidence and mortality rates at 5 years old. The incidence rate was lower after the cessation of the NB mass screening program. There was no substantial change in the mortality rate, and no significant variation in the relative 5-year survival between groups. The cumulative incidence rate in the latter cohort was significantly lower than that in the former cohort (rate ratio: 0.39, 95% CI: 0.25-0.61, p < 0.001). No significant difference in the cumulative mortality rate between the two cohorts was observed (rate ratio: 0.99, 95% CI: 0.80-1.22, p = 0.93). The NB incidence rate decreased markedly and the mortality rate did not substantially change after the cessation of the NB mass screening program. The NB mass screening program probably caused overdiagnosis, and its effectiveness was not clear.