PROGNOSTIC-SIGNIFICANCE OF MULTIPLE GENETIC LESIONS ON CHROMOSOME-19,CHROMOSOME-10, AND CHROMOSOME-17 IN OLIGODENDROGLIOMAS

Patients diagnosed with oligodendrogliomas/oligoastrocytomas and with somatic loss of genes on chromosome 19q13.2-q13.3 survived for >5-6 ye ars, a survival period typical of the tumors of oligodendroglial origi n. One patient with oligoastrocytoma, harboring allelic loss on chromo some 10p in the tumor DNA, had a recurrence five years later with prog ression to anaplastic astrocytoma. However, another patient with oligo astrocytoma, whose tumor suffered multiple genetic lesions on chromoso mes 19q13.2-13.3, 10q22-24, and 17p13.1 (a point mutation in the p53 g ene), had two subsequent recurrences as anaplastic astrocytomas and a survival period of 29 months. Our data suggest that in tumors of oligo dendroglial origin the inactivation of a tumor suppressor gene on chro mosome 10, especially in conjunction with other genetic aberrations, i s indicative of aggressive clinical course.