Cytogenetic analysis of a malignant triton tumor and a malignant peripheral nerve sheath tumor and a review of the literature.

Cytogenetic analyses of malignant peripheral nerve sheath tumors (MPNST) and malignant triton tumors (MTT) are few to date. Two separate triton tumor specimens from one patient and a MPNST specimen from another patient, both with peripheral neurofibromatosis (NF-1, von Recklinghausen disease), showed complex near-triploid complements and partial deletion of the short arm of chromosome 1. Notably, a structural abnormality of chromosome 17 was detected in the MPNST, and loss of chromosome 22 was detected in the MTT. The genes for peripheral neurofibromatosis (NF-1) and central neurofibromatosis (NF-2) have been mapped to these two chromosomes respectively.