Cytogenetic features of neonatal leukemias

We reviewed a series of 41 neonatal leukemias (NL), including published cases karyotyped by banding techniques, but excluding Down syndrome-associated cases and analyzed distribution of cytogenetic anomalies with respect to other clinical variables and outcome. The most frequent chromosomal changes in this age group involve rearrangements of 11q23, which is correlated with high white blood cell (WBC) count at onset and type of leukemia. A discrete heterogeneity of cytogenetic abnormalities is also evident, however, possibly reflecting other specific pathways in NL development. With respect to prognosis, cytogenetic abnormalities are a strong indicator of poor prognosis.