Breast Cancer: HER-2 FISH (PathVysion™)

Indications For BREAST CANCER: HER-2 FISH (PathVysion™)

This blood test allows identification of HER-2 over expression by immunohistochemistry in conjunction with gene amplification detected by FISH is associated with a comprehensive positive response to the humanized, monoclonal antibody Herceptin® in patients that have failed standard chemotherapy treatment. The detection of HER-2/neu gene amplification by FISH analysis is linked with rapid cancer cell proliferation, decreased disease-free survival and poor overall survival in both node-negative and node-positive ductal breast cancers. In patients with advanced breast carcinoma, HER-2 amplification predicts responsiveness to transtuzumab (Herceptin®) therapy and poor response to standard chemotherapy.

Collection Procedure
Fixed Paraffin Block with Corresponding H&E:

  • Tissue should be well fixed and well processed. Formalin fixation preferred unless otherwise indicated. If alternative fixative is used, it should be noted on requisition
  • 0.2cm x 0.2cm x .2cm tissue
  • Store specimen at room temperature (>16°)

Specimen Requirements
Unstained Slides:

  • Send all slides within 6 weeks of cutting
  • Minimum of 4 slides for FISH testing
  • Pre-cut slides from paraffin block in 5 micron sections and mounted on poly-l-lysine coated or plus (+) slides
  • IHC+ region indicated and IHC score
  • Air dry. Do not oven dry
  • Store specimens at room temperature (>16°)

Specimen Container
Send slides in protective case to prevent damage.

Methodology
Laboratory testing for HER-2/neu gene amplification involves Microscopic analysis, digital image capture

Causes for Rejection
Inappropriate processing of tissue or IHC negative result

Transport
Room temperature

Turnaround Time
2-3 days