Herceptest (HER2)

I HER2

Test Synonym:

HER2-neu, Immuno, Immunohistochemistry, Immunoperoxidase

Test Synonym:

88360 – Morphometric analysis, tumor immunohistochemstry

Turnaround Time:

3 days

Methodology:

Immunohistochemistry

Specimen Requirements:

Formalin fixed paraffin embedded tissue block

Causes for Rejection:

Improper specimen labeling; insufficient sample; inadequate fixation and/or processing

Specimen Stability:

Indefinitely

Storage and Handling:

Ship blocks at ambient temperature

Reference Range:

Normal breast tissues may produce positive reactivity scoring 1+ intensity, as will kidney, uterus and epithelium of the colon, stomach and small intestine.  Normal tissues producing 2+ to 3+ staining intensity include esophageal epithelia, Langerhans cells, pituitary endocrine cells, prostate and squamous epithelia of tonsil.

Indication:

In a fraction of patients with breast cancer, the HER2 protein is over expressed as part of the process of malignant transformation and tumor progression.  Overexpression of the HER2 protein on the surface of breast cancer cells suggested that it could be a target for antibody therapy, Herceptin (Trastuzumab)

References:

1. Coussens L, et al. (1985). Tyrosine kinase receptor with extensive homology to EGF receptor shares chromosomal location with neu oncogene. Science 230:1132-9.
2. King CR, Kraus MH, Aaronson SA. (1985). Amplification of a novel v-erbB-related gene in a human mammary carcinoma.  Science 229:974-6