Cytogenetic characterization of three malignant peripheral nerve sheath tumors.

Malignant peripheral nerve sheath tumors (MPNST) are soft tissue sarcomas occurring frequently in patients with neurofibromatosis 1. We present three fully karyotyped cases of MPNST revealing aberrant near-triploid karyotypes. In all three cases we found deletions of chromosome arms or chromosomes 1p, 10q, 9, and 15, as well as gain of chromosome 7 in two NF1-associated cases and gain of chromosome 8 in an NF1-associated and a sporadic case. The chromosomal region of the NF1 gene was cytogenetically unchanged in all cases, whereas two MPNST cases showed losses of the region 22q harboring the locus of the NF2 gene.