Molecular genetic aspects of oligodendrogliomas including analysis by comparative genomic hybridization

Oligodendroglial neoplasms are a subgroup of glio-mas with distinctive morphological characteristics. In the present study we have evaluated a series of these tumors to define their molecular profiles and to de-termine whether there is a relationship between mo-lecular genetic parameters and histological pattern in this tumor type. Loss of heterozygosity (LOH) for 1p and 19q was seen in 17/23 (74%) well-differentiated oligodendrogliomas, in 18/23 (83%) anaplastic oligo-dendrogliomas, and in 3/8 (38%) oligoastrocytomas grades II and III. LOH for 17p and/or mutations of the TP53 gene occurred in 14 of these 55 tumors. Only one of the 14 cases with 17p LOH/TP53 gene mutation also had LOH for 1p and 19q, and significant astro-cytic elements were seen histologically in the major