Association of chromosome 10 losses and negative prognosis in oligoastrocytomas.

Oligoastrocytomas are mixed gliomas harboring different genetic alterations and with heterogeneous clinical evolution. We have looked for correlations between genetic losses and clinical evolution in 34 oligoastrocytomas. Loss of heterozygosity (LOH) with different microsatellite markers was studied on chromosomes 1p, 10q, 17p, and 19q. LOH on 1p was found in 44% of the tumors, on 10q in 24%, on 17p in 18%, and on 19q in 38%. LOH on 1p and 19q was combined in 29% of the patients. LOH on 1p was associated with significantly longer overall survival (p = 0.0092) and LOH on 10q with shorter overall survival (p = 0.0206). The observation that LOH on 10q predicts a short survival in oligoastrocytomas is novel and provides further evidence that genetic analysis may help to predict the clinical evolution of different gliomas, giving a more rationale basis to therapeutic options.