Molecular karyotyping in sarcoma diagnostics and research.

Conventional cytogenetic and molecular genetic studies have both clinical and biological significance in sarcomas. However, the resolution of these methods does not always suffice to screening of novel, specific genetic changes, such as small deletions, amplifications, and fusion genes. Tumor-specific chromosomal translocations revealed by cytogenetic and molecular methods play a decisive role in the differential diagnosis of sarcomas. The novel molecular karyotyping techniques have proven to be powerful in the screening of clinically and biologically relevant molecular changes in human neoplasias. A variety of platforms for molecular karyotyping is available, e.g., arrayed cDNA clones or oligonucleotides that can be used in microarray-based comparative genomic hybridization (CGH) and gene expression analysis. We review here the clinically most relevant cytogenetic and molecular changes in sarcomas and describe latest microarray techniques for screening of clinically relevant gene copy number and expression changes.