Amplification of HER-2(erbB-2/neu) oncogene as the most significant prognostic factor in a group of Russian breast cancer patients

Abstract

Amplification of HER-2(erbB-2/neu) oncogene was detected in 36 of 142 (25%) breast carcinomas (BC) RNA expression was examined in 42 carcinomas, in 10 of them overexpression was revealed. Amplification was matched by overexpression. No association was found between the increased number of HER-2(erbB-2/neu) copies and tumor size, lymph node involvement, stage of disease, age of onset, and estrogen and progesterone receptor level. HER-2(erbB-2/neu) amplification was shown to be of independent prognostic significance in the group of 32 BC patients with sufficient follow-up (more than 40 months). Six of 7 HER-2(erbB-2/neu) amplification-positive patients and only 2 of 25 HER-2(erbB-2/neu) amplification-negative ones relapsed (p < 0.00005).