Cytogenetic and molecular analysis of pediatric neoplasms: diagnostic and clinical implications

Recurring chromosome changes, particularly those closely associated with specific subtypes of tumors, have provided critical clues to the location of the genes involved in the genesis of these tumors. These, in turn, have led to the cloning of these genes, especially those located at translocation breakpoints in leukemias, lymphomas, and sarcomas. The immediate consequence of the cloning of these genes is to provide DNA probes for various diagnostic tests, including standard Southern blot analysis, the polymerase chain reaction, and fluorescence in situ hybridization. Because many of these chromosome rearrangements are associated with either an improved or a poorer survival, karyotypic abnormalities provide prognostic information. In the future, more sophisticated understanding of the genes involved and of the nature of their altered function should lead to improved therapy.