Multiple cytogenetic aberrations in neurofibrosarcomas complicating neurofibromatosis.

Four neurofibrosarcomas, from four unrelated patients with Von Recklinghausen's neurofibromatosis, demonstrated multiple cytogenetic aberrations characterized by loss of chromosomes and/or polysomy, as well as multiple structural abnormalities of diverse types. These observations are noteworthy for two reasons. First, the widespread and varied nature of the chromosomal changes indicate that, in at least these instances, the transformation of a benign neurofibroma to a neurofibrosarcoma may well involve a substance having an affect at multiple chromosomal sites. Second, efforts to investigate neurofibrosarcoma pathogenesis using direct analysis of DNA structure and gene activity in neurofibrosarcomas must first take into account the chromosomal distortions characterizing each tumor.