Cytogenetic evaluation of childhood neoplasms.

The cytogenetics of childhood neoplasms are reviewed. Chromosome abnormalities specific for various pediatric neoplasms can provide diagnostic, prognostic, and scientific information of value to the pathologist, clinician, and molecular biologist. Karyotypes of acute leukemia have independent prognostic significance. Chromosome aberrations associated with several of the small round blue-cell tumors of childhood can clarify the diagnosis. Recurring abnormalities in several tumors, such as hepatoblastomas, primitive neuroectodermal tumors, fibrosarcomas, and other tumor types, suggest interesting questions about pathogenesis and histogenetic relationships. Several tumor-specific chromosome aberrations, mostly in the acute leukemias, have been characterized at a molecular level.