Finally, we observed that TOP2A amplification only occurred in conjunction with erb-B2 amplification in our paraffin-embedded cases of invasive breast carcinoma and that this event was present in 5 (42%) of 12 erb-B2 amplified cases.
The characteristics are compared to findings on paired ERBB2 and TOP2A data from 649 patients with invasive breast cancer from a previously published biomarker study.