Name: HER2 Dual ISH DNA
Test Name: HER2 Dual ISH DNA
Health Link Test Code: HCPATHS
LIS Test Code: AP5
CPT Code(s): 88377
Methodology: Dual In Situ Hybridization (ISH)
Days Performed: Mon-Fri.
In-Lab Turnaround Time: 1 week.
Specimen: Formalin-fixed, paraffin embedded tissue.
Tissue specimens should be immersed in fixative within one hour of the biopsy or resection procedure.
Specimens must be fixed in 10% neutral buffered formalin for 6-48 hours.
The volume of formalin should be at least 10 times the volume of the specimen.
FFPE tissue containing tumor should be cut in 4-micron sections on slide.
Transport in formalin at room temperature.
Specimens processed in alternative fixatives or with alternative fixative durations. Decalcification solutions with strong acids should not be used.
Non-amplified (HER2/Chr17 ratio less than 2.0)
Tissue staining is dependent on the handling and processing of the tissue prior to staining. Improper fixation, freezing, thawing, washing, drying heating, sectioning or contamination with other tissues or fluids may produce artifacts. Inconsistent results may be a consequence of variations in fixation and embedding methods or inherent irregularities within the tissue.
The clinical interpretation of any positive staining, or its absence, must be evaluated within the context of clinical history, morphology and other histopathological criteria.
UWHC Policy 7.01 Pathology Specimen Care and Handling describes the requirements for submission, identification, handling and release of tissue specimens including exemptions and guidelines for limited examination.
Interpretation provided as an addendum to original pathology report located in the Health Link Path tab.
Specimens with equivocal HER2/Chr17 ratios and decalcified tissues will be reflexed for Her2/neu immunohistochemistry staining.
The presence of HER2 gene amplification predicts a favorable response to trastuzumab.