Test Directory

• HER2(ERBB2), 17q12
• 17cen, 17p11.1-q11.1

Gastric cancer is the fifth most common cancer worldwide and 15th in the US with ~ 25,000 new cases annually. The human epidermal growth factor receptor 2 oncogene (HER2) (also known as ERBB2), is located on chromosome 17q and is a tyrosine kinase that belongs to a family of transmembrane receptor

proteins, which include EGFR/HER1, HER2, HER3, HER4.

The HER family of proteins are involved in regulation of cell growth, survival, and differentiation of cells. Amplification and/or overexpression of HER2 is reported in approximately 25 - 30 % of breast cancer patients and 20 – 33% of gastric cancers.

Amplification of HER2 is associated with aggressive disease and shorter disease-free survival in both breast and gastric cancer.

Patients that demonstrate amplification of HER2 may be candidates for treatment with chemotherapeutic agents that target the HER2 protein. This test provides HER2 amplification status to aid in determining anti-HER2 targeted therapies for patients.

Specimen: Formalin-Fixed Paraffin Embedded Tissue Block or 2 slides from a FFPET block, cut at 4 - 5 micron thickness and mounted on charged lysine slides with accompanying H&E slide identifying the region(s) of interest (ROI).

Specimen should have an ischemia time of < 1 hour and a total formalin fixation time between 6 - 72 hours.

• Each specimen must be accompanied by a requisition form, script, electronic order or physician note.
• Each order must indicate the reason for testing (Diagnosis).

Transport to the laboratory at room temperature.

• Specimen arriving without any form of patient identification (unlabeled)
• FFPET sections that are not properly attached to the slide
• FFPET sections with excessive cracks, splits or deterioration that would inhibit analysis
• Broken FFPET slides

• Breast specimens are evaluated based upon the most recent ASCO/CAP guidelines. Amplification of the HER2 gene is defined as a HER2 (ERBB2)/CEP17 ratio greater than or equal to 2.0. Non-amplification of the HER2 gene is defined as a HER2 (ERBB2)/CEP17 ratio of less than 2.0.
• Gastroesophageal adenocarcinoma (GEA) specimens are evaluated based upon the most recent CAP/ASCP/ASCO guidelines. Amplification of the HER2 gene is defined as a HER2 (ERBB2)/CEP17 ratio greater than or equal to 2.0 or an average number of HER2 (ERBB2) signals per cell greater than or equal to 6.0.
• Colorectal specimens are evaluated as having amplification of the HER2 gene if more than 50% of the cells analyzed have a HER2 (ERBB2)/CEP17 ratio of greater than or equal to 2.0.

• FISH HER2/ Neu
• HER2/17cen
• HER2
• ERBB2