title: Neuroblastoma screening in Japan: population-based cohort study and future aspects of screening.
abstract: BACKGROUND
  It is unknown whether screening for neuroblastoma has the benefit of reducing the incidence of advanced diseaseor mortality due to neuroblastoma.Japanese nationwide massscreening for 6 month old infants was launched in 1985 and was performed using quantitative high-performance liquid chromatography (HPLC) between years 1990 to 2003.
  
  
  METHODS
  We compared the incidence rates (IR) and the mortality rates (MR) per 100,000 births of neuroblastomas diagnosed before 6 years of age between 2 cohorts: children born during the years 1980 to1984 (Pre-screen cohort, n = 7,620,203) and 1990 to1998 (Screen cohort, n = 10,878,918). We then proposed the optimal timing and procedures for future screening.
  
  
  RESULTS
  Cumulative IR in the Screen cohortwas significantly higher than the Pre-screen cohort (29.80 vs. 11.96, P <0.0001). On the other hand, IR of neuroblastoma diagnosed after 24 months old in the Screen cohort was significantly lower than in the Pre-screen cohort (P <0.0001). The cumulative MR of the Pre-screen cohort was 5.35, whereas that of the Screen cohort was 2.82 (P <0.0001).
  
  
  CONCLUSIONS
  HPLC mass-screening for neuroblastoma at 6 months of age found a marked increase in incidence in younger children (less than 12 month old) and a significant decrease in mortality rates overall. To reduce overdiagnosis of regressing cases and to identify preclinical stages of unfavourable cases, we propose using HPLC-screening at 18 months of age.
authors.affiliation: Department of Pediatric Surgery, Hiroshima University Hospital, Natural Science Center for Basic Research and Development, Hiroshima University, 1-2-3, Kasumi, Minami-ku, Hiroshima, 734-8551, Japan. eiso@hiroshima-u.ac.jp
authors.forename: Eiso
authors.initials: E
authors.lastname: Hiyama
mesh_terms: D002648:Child; D002675:Child, Preschool; D002851:Chromatography, High Pressure Liquid; D015331:Cohort Studies; D005544:Forecasting; D006801:Humans; D015994:Incidence; D007223:Infant; D007564:Japan; D008403:Mass Screening; D009447:Neuroblastoma / Q000175:diagnosis* / Q000453:epidemiology