Classical gene amplifications in human breast cancer are not associated with distant solid metastases.

To determine the relationship between breast cancer progression and gene amplification, we screened 62 distant metastases and 122 primary breast tumours for the amplification of the proto-oncogenes MYC and ERBB2 and the 11q13 chromosomal region. Surprisingly, solid metastases showed an absence of gene amplification. These results suggest that the amplification of the proto-oncogenes MYC and ERBB2 and the 11q13 chromosomal region seem to be involved mainly in the genesis of the primary breast tumour rather than its progression.