ADDITIONAL COPIES OF 1Q IN SEQUENTIAL SAMPLES FROM A PHYLLODES TUMOR OF THE BREAST

Cytogenetic and fluorescent in situ hybridization (FISH) analysis has been performed on consecutive samples, taken 4 weeks apart, from a phy llodes breast tumor. This revealed the presence of two different chrom osome 1 derivatives, namely a dic(1;10)(q10;q24) in the first sample a nd an i(1)(q10) in the second. In one cell out of 25 from the second s ample both derivative chromosomes were seen. A chromosome 21 was lost in both samples. These results are consistent with phyllodes tumors ha ving a clonal origin.