Lack of microsatellite instability in giant cell tumor of bone.

Microsatellite instability was searched for at six different loci on chromosome arms 5q, 18q, 15q, 17p, 19q, and 11p in 22 patients (12 men and 10 women; average age of 31.8 years, range of 20-55 years) with giant cell tumor of bone (GCT). These loci were chosen because of their use in microsatellite instability studies in other tumors such as colorectal cancer (e.g., 5q, 18q, 17p) or because of the presence of chromosomal abnormalities such as telomeric associations commonly occurring at 19q and 11p termini (thus the reason for including the 19q and 11p termini microsatellites in our study of GCT). No microsatellite instability or loss of heterozygosity were detected when comparing normal and tumor cells from any of the GCT patients. Unlike several other tumors, our study indicates that microsatellite instability does not appear to play a role in the tumorigenesis of GCT although other abnormal cytogenetic, biochemical, and molecular genetics data do exist for this musculoskeletal tumor.