FISH ANALYSIS, HER2/neu AMPLIFICATION ASSOCIATED WITH GASTROESOPHAGEAL CANCER
Pseudonyms: HER-2, HER-2/neu, ERBB2, c-erb-b2, Esophageal Cancer, Gastric Cancer, Gastro-esophageal Cancer
TURNAROUND TIME: 7 days
TESTING METHODOLOGY: Fluorescence in situ hybridization
- Collect: Tumor tissue
- Specimens: Paraffin-embedded, formalin-fixed (FFPE) tissue block or five 4 µm sections on positively-charged glass slides including one consecutive hematoxylin and eosin-stained (H and E) section with the tumor areas marked. Optimal fixation should be between 6 and 48 hours in 10% neutral buffered formalin. Do not oven dry the slides
- Stability: Paraffin block: ambient temperature, indefinite
- Unacceptable Conditions: Tissue not verified for the presence of tumor by a pathologist; specimens fixed or processed in fixatives other than formalin
A FISH HER-2 Specimen Submission must accompany the specimen. Contact the Cytogenetics Laboratory at 918-502-1722 to obtain further information
Test Summary: Fluorescence in situ hybridization (FISH) analysis is designed to determine the presence of amplification of the HER2/neu oncogene in primary or metastatic gastroesophageal tumors.
Method: A dual-color FISH analysis performed on interphase nuclei using the PathVysion probe set (Abbott Molecular) including HER2/neu gene probe and the D17Z1 probe for chromosome 17; analysis of 20 to 40 interphase nuclei from tumor cells.
Interpretation: HER2:CEP17 ratio >2.2 indicates HER2 amplification, a HER2:CEP17 ratio of 1.8 to 2.2 is considered equivocal, and HER2:CEP17 ratio of <1.8 is considered not amplified.
Reference Values: An interpretive report will be provided. The results are interpreted using the American Society of Clinical Oncology/College of American Pathologists guidelines (2007) and the guidelines from the ToGA clinical trial.
FDA Approval: This application of the PathVysion HER2 FISH test is not approved by the FDA and should be used as an adjunct to other clinical and pathological information.
Indications for Use:
- Identify the presence of HER2 amplification in patients with gastroesophageal cancer.
- Determine the HER2 gene status in gastroesophageal cancer specimens with HER2 over-expression or equivocal expression by immunohistochemistry.
- Prognostic indicator for patients with gastroesophageal cancer.
- Guide therapy decisions for patients with gastroesophageal cancer for whom Herceptin (Trastuzumab) treatment is being considered.