Effects of the Cessation of Mass Screening for Neuroblastoma at 6 Months of Age: A Population-Based Study in Osaka, Japan.

ABSTRACT

BACKGROUND: In 2004, the Japanese government halted the 6-month mass screening program for neuroblastoma. We investigated whether its cessation had led to an increase not only in mortality due to this disease but also in the incidence of advanced-stage disease among older children. METHODS: Study subjects were neuroblastoma patients retrieved from the population-based Osaka Cancer Registry. Trends of incidence and mortality from neuroblastoma were analyzed by calendar year and birth cohort. Prognostic factors, including stage and v-myc avian myelocytomatosis viral oncogene neuroblastoma derived homolog (MYCN) oncogene status, were compared before and after the cessation of mass screening. RESULTS: Age-standardized incidence rates in 2005-2009 (the cessation period of mass screening; 11.1 per million) were similar to those in 1975-1979 (the pre-screening period; 8.6 per million). Age-standardized mortality rates tended to decrease from 1975-1979 (4.0 per million) to 2005-2009 (2.7 per million) in parallel with the improvement in survival. Analysis by birth cohort indicated that the mortality rates in 2004-2005 (after cessation) for children 0-4 years of age were lower than those in 1975-1979 (OE ratio 0.25; 95% confidence interval, 0.03-0.90). For children 1-9 years of age, there was a not significant difference in the distribution of stage, MYCN oncogene status, and DNA ploidy between 1991-2003 (the mass screening period) and 2004-2008 (after cessation). CONCLUSIONS: The cessation of mass screening for neuroblastoma does not appear to have increased mortality due to this disease or incidence of advanced-stage disease among older children.