HER2
17q
The HER2 gene, located on 17q, encodes a 185-kD transmembrane tyrosine kinase receptor. Amplification of this gene with overexpression of the gene product occurs in about 30% of cases of breast cancer and is considered to be a poor prognostic indicator for this tumor.
HER2 is an important predictive marker for response to trastuzumab and lapatinib in breast cancer. It is also a powerful prognostic marker in node-positive patients.
Although the assessment of HER2 expression is most important for predicting response to anti-HER2 therapy, detection of low-level HER2 expression might also be useful in helping to select a more aggressive treatment regimen for patients ineligible for anti-HER2 therapy. (#19252432#)
Pathology
HER-2/neu gene amplification (HER2 amplification) in
- breast cancer (mammary carcinomas)
- gastric cancer (gastric carcinomas)
References
HER-2 amplification is highly homogenous in gastric cancer. Bilous M, Osamura RY, Rüschoff J, van de Vijver M, Hanna W, Penault-Llorca F, Roche P. Hum Pathol. 2009 Nov 13. PMID: #19914678#
Even low-level HER2 expression may be associated with worse outcome in node-positive breast cancer. Gilcrease MZ, Woodward WA, Nicolas MM, Corley LJ, Fuller GN, Esteva FJ, Tucker SL, Buchholz TA. Am J Surg Pathol. 2009 May;33(5):759-67. PMID: #19252432#