Z.V. and J.Z. contributed equally to the work.
Preferential HER-2/neu overexpression and/or amplification in aggressive histological subtypes of invasive breast cancer
Article first published online: 26 MAR 2004
Volume 44, Issue 4, pages 332–338, April 2004
How to Cite
Varga, Z., Zhao, J., Öhlschlegel, C., Odermatt, B. and Heitz, P. U. (2004), Preferential HER-2/neu overexpression and/or amplification in aggressive histological subtypes of invasive breast cancer. Histopathology, 44: 332–338. doi: 10.1111/j.1365-2559.2004.01843.x
- Issue published online: 26 MAR 2004
- Article first published online: 26 MAR 2004
- Date of submission 6 June 2003 Accepted for publication 30 September 2003
- breast cancer;
- special type;
- unfavourable prognosis;
Aims: To investigate whether alterations of the HER2 gene occur more frequently in histologically unfavourable subtypes of invasive breast cancer.
Methods: The study was composed of nine invasive apocrine, six lipid-rich, 12 glycogen-rich, 11 micropapillary and 33 pleomorphic lobular breast carcinomas. Lymph node involvement was represented in all subgroups. HER2 status was confirmed in all cases by using immunohistochemistry (CB11, Herceptest) and fluorescent in-situ hybridization (FISH) analysis (Vysis).
Results: Micropapillary and apocrine carcinomas showed the highest rate of protein overexpression (72% and 66%) and gene amplification (45% and 44%). Protein overexpression was common in poorly differentiated pleomorphic lobular carcinomas (56%); however, this subgroup failed to show an increased number of gene copies by FISH (31%). The incidence of HER2 overexpression (33% and 50%, respectively) and gene amplification (25% and 33%, respectively) among glycogen-rich and lipid-rich carcinomas was not higher than that observed in breast cancer generally.
Conclusion: Our data suggest that preferential involvement of the HER2 gene in micropapillary and apocrine breast carcinomas may contribute to their aggressive behaviour.