Diagnostic and molecular implications of specific chromosomal translocations in mesenchymal tumors

In many tumors of mesenchymal origin specific chromosomal translocations are a consistent finding not restricted to malignant tumors. Often the genes behind those translocations have been identified. Rarely, gene activating per se is sufficient to contribute to or cause tumorigenesis whereas in most cases the two genes of the translocation partners both contribute to the formation of a newly arisen fusion gene, thus enabling the detection of resulting chimeric transcripts by highly sensitive techniques. Genes participating in translocations may be affected in more than one tumor entity, such as e.g. HMGIC in a variety of benign mesenchymal tumors and EWS in a couple of malignant mesenchymal tumors. Certainly, the identification and molecular characterization of specific chromosomal translocations will not only allow for important insights highlighting the process of tumorigenesis but offer also promising new tools to obtain more refined data of diagnostic as well as of prognostic importance.