Reference Interval:
Criteria for intensity of cell membrane staining with PATHWAY® HER-2/neu:
| Grade
| Interpretations
| Microscopic Finding
| | 0
| Negative
| No staining is observed in invasive tumor cells.
| | 1+
| Negative
| Weak, incomplete membrane staining in any proportion of invasive tumor cells, or weak, complete membrane staining in less than 10% of cells.
| | 2+
| Equivocal
| Complete membrane staining that is nonuniform or weak but with obvious circumferential distribution in at least 10% of cells, or intense complete membrane staining in less than 30% of tumor cells.
| | 3+
| Positive
| Uniform intense membrane staining of
more than 30% of invasive tumor cells.
| |
|
| Interpretive Data: |
The results of the Ventana PATHWAY® anti-HER2/neu (4B5) rabbit monoclonal assay are interpreted in a semi-quantitative manner. Assay is performed on paraffin-embedded, formalin-fixed tissue. Antibody clone is 4B5 and uses a biotinylated detection system.
ARUP Laboratories uses the ASCO/CAP criteria for interpretation of HER2 protein expression. Positive cases are those with uniform intense membrane staining of more than 30% of invasive tumor cell (Score 3+). Negative cases are defined as no staining (Score 0) or weak, incomplete membrane staining in any proportion of invasive tumor cells, or weak, complete membrane staining in less than 10% of cells (Score 1). Equivocal cases are those with complete membrane staining that is nonuniform or weak but with obvious circumferential distribution in at least 10% of cells, or intense complete membrane staining in 30% or less of tumor cells (Score 2).
For more information refer to the ASCO/CAP guidelines found at http://www.jco.org.
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| CPT Code(s): |
88360
|
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