A cytogenetic analysis in two cases of malignant peripheral nerve sheath tumor showing hypodiploid karyotype.

In this study, we report cytogenetic findings in two cases of malignant peripheral nerve sheath tumor (MPNST) with hypodiploid karyotypes. A G-band technique, multicolor fluorescence in situ hybridization (m-FISH) and comparative genomic hybridization (CGH) were used and compared in this investigation. In both tumors, the G-band and m-FISH analysis demonstrated multiple rearrangements on chromosomes 1-5, 8-12, 15-17, 20 and 21, whereas CGH exhibited gains at 8q and 4q. Both of the structural aberrations and the genomic imbalances of the chromosomes may play an important role in the pathogenesis and development of MPNST. No cytogenetic abnormalities specific for MPNST were found in the present cases or in other previously reported cases. This may reflect the diversity or heterogeneity of MPNST that exhibit various clinical and histological features. However, there are few cases described in detail on a morphologic pattern of MPNST, a correlation between the cytogenetic aberrations and the histologic patterns are still uncertain.