Objective: The aim of the present study was to report the chromosomal abnormalities findings in rare pediatric mixed glioneuronal tumor (GNT), which could not be classified according to the WHO classification.
Methods: Cytogenetic studies were performed using G-banding and fluorescence in situ hybridization (FISH) techniques.
Results: Cytogenetic analyses showed a deletion of 1p as primary genetic event and gain of chromosome 7 as secondary change. Furthermore, we present a review of available cytogenetic data of 72 pediatric patients with GNT. Taken into account these data and the present case, we found that the most frequent chromosomal anomalies involved gains of chromosomes 7 (15.1%), 5 (8.2%), 1q32-qter (6.8%), 8p21-qter (6.8%), 12 (5.5%), 18 (5.5%), 20q11-qter (5.5%), and X (5.5%). Frequent losses were detected on chromosome regions 1p (8.2%) and 22q (5.5%).
Conclusion: The findings of our case combined with those of previous reports suggest that chromosomes 1 and 7 may contain candidate genes involved in the tumorigenesis of GNT.