MYCN Amplification in Pediatric Brain Tumors: Detection by Differential Polymerase Chain Reaction

MYCN amplification is frequently observed in tumors such as neuroblastomas, but is uncommon in pediatric brain tumors, which represent the most common solid tumors of childhood. MYCN amplification is rarely described in gliomas and some primitive neuroectodermal tumors (PNETs) of the central nervous system. Oncogene amplification has traditionally been determined quantitatively by Southern blotting, a time consuming technique often requiring more DNA than is available from small brain tumor biopsies. We applied the novel technique of differential polymerase chain reaction (PCR) to a small series of 8 pediatric brain tumors to assess the presence of MYCN amplification. The tumors included 4 cerebellar PNETs, 1 cerebral PNET, 1 malignant glioma, 1 subependymal giant cell tumor, and 1 ganglioglioma. Differential PCR showed MYCN amplification in 1 cerebellar PNET and 1 malignant glioma, with amplification 20-fold and 80-fold, respectively, above diploid controls. Our results confirm that differential PCR is a useful technique to assess oncogene amplification in pediatric brain tumors. (The J Histotechnol 20:115, 1997)