Her2 Testing in Breast Cancer

Purpose of the test

The Her2 gene codes for a transmembrane growth factor receptor. Gene amplification and consequent overexpression of Her2 occurs in around 20% of women with breast cancer and is associated with an adverse prognosis. Trastuzumab (Herceptin® :Roche) is a chimeric antibody (95% human and 5% murine) developed against the Her2 protein. In HER2-positive metastatic disease trastuzumab alone has been shown to achieve a clinical response in around 35% of patients as first line treatment and significantly prolongs survival in combination with Paclitaxel and Docetaxel.

Sample Requirements

Her2 over-expression can be demonstrated by immunocytochemistry on paraffin processed tissue in most cases. However equivocal results can occur in a proportion of cases when demonstration of the gene amplification itself by FISH will clarify the result. Tissue which has been decalcified is not suitable for FISH.

Storage and Transport

First class post within 4 days (temperature not to exceed 30°C during transport)

If possible, please complete the request form attached and send as a hard copy (do not send electronically) with the sample. This will ensure all relevant information is available and will aid us in processing your test.