ARUP's Laboratory Test Directory

0049168: C-erb B-2 (HER-2/neu) with Reflex to HER-2/neu by FISH if 2+ or 3+

Test Mnemonic: CERB23 IP
Methodology: Immunohistochemistry

Performed: Mon-Fri

Reported: 1-5 days
Reflexed to HER2FISH (0049218) as requested, FISH assay will be performed and reported within 4-12 days, if no repeats are required.

Specimen Required:  
Collect: Tumor Tissue

Transport: Paraffin-embedded, formalin-fixed tissue block enriched with tumor at 20-25°C. Protect paraffin block from excessive heat. Ship in a cooled container during summer months. Include surgical pathology report.

Unacceptable Conditions: Paraffin block with no tumor tissue remaining. Samples fixed in formalin substitute.

Stability: Ambient: Indefinitely; Refrigerated: Acceptable; Frozen: Unacceptable

Reference Interval:
The results of this assay are interpreted in a semi-quantitative manner. These results are given as 0 to 3+ with the following definitions and interpretations:
 
Grade Interpretation Microscopic Finding
0 Negative No staining is observed or membrane staining is observed in less than 10% of the tumor cells.
1+ Negative Faint or blush staining involving a portion of the circumference of the cytoplasmic membrane in more than 10% of the neoplastic cell population.
2+ Positive Weak but definitive staining of the membrane over 100% of the cytoplasmic circumference in more than 30% of the neoplastic cell population.
3+ Positive Strong positive staining of the membrane over 100% of the cytoplasmic circumference in more than 30% of the neoplastic cell population.
Note: A 2+ or 3+ result will be confirmed by FISH testing. FISH results should be considered definitive.

Interpretive Data:
The immunohistochemical test traditionally used by ARUP for the assessment of HER2/neu appears to have prognostic and predictive significance but is not FDA approved as a prognostic indicator or as a triage test for Herceptin therapy.

The results of this assay are interpreted in a semi-quantitative manner.

Assay is performed on Paraffin-embedded, formalin-fixed tissue. Antibody clone is 3B5 and the detection system is LSAB.

Please refer to Statement B in the Compliance Statements section in the front of the Laboratory Test Directory.



Note:
ARUP also offers the HercepTestby DAKO (IHC), and PathVysionby Vysis (HER-2/neu by FISH (PathVysionHER-2)), which are FDA approved as triage tests for Herceptin therapy (predictive indicator). To order these tests, refer to HercepTestTissue Assay, Paraffin (0049174) or HER-2/neu by FISH (Manual) (0049218).

If C-erb B-2 result is 2+ or 3+, then HER-2/neu by FISH will be added.

CPT Code(s):
88360; if reflexed add 88368 x2