Microsatellite instability was searched for at six different loci on c
hromosome 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 gi
ant cell tumor of bone (GCT). These loci were chosen because of their
use in microsatellite instability studies in other tumors such as colo
rectal cancer (e.g., 5q, 18q, 17p) or because of the presence of chrom
osomal 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 insta
bility or loss of heterozygosity were detected when comparing normal a
nd tumor cells from any of the GCT patients. Unlike several other rumo
rs, our study indicates that microsatellite instability does not appea
r to play a role in the tumorigenesis of GCT although other abnormal c
ytogenetic, biochemical, and molecular genetics data do exist for this
musculoskeletal tumor.