[Neuroblastoma; biology and prognostic factors].

Recently accumulated data on the biology of the tumors of neuroblastoma group are reviewed. Histopathological classification system developed by Shimada et al, elevated levels of serum neuron-specific enolase and ferritin, and gene abnormalities including partial deletion of the short arm of chromosome #1 and N-myc gene amplification are discussed as well as their prognostic significance. Also, the current activities of CCSG (Childrens Cancer Study Group) neuroblastoma studies are briefly reported.