Molecular pathology of human neuroblastomas.

Several genetic features have been identified that are characteristic of neuroblastomas. These include hyperdiploidy, deletion of 1p, amplification of N-myc, and expression of the neurotrophin receptor, TRK-A. These genetic characteristics allow neuroblastomas to be categorized into three subtypes, with distinct clinical features and behavior. In the past, neuroblastoma had been considered to be a disease with a better outcome if diagnosed early. However, it is now apparent that the tumors occurring in infants are genetically different than those in older children, and a genetically favorable subtype seldom, if ever, evolves into an unfavorable one. Different approaches may be necessary for each subtype, and the molecular pathology of the tumor may be better at predicting outcome than patient age and disease stage.