HercepTest ™ (HER2/Neu) Image Quantitation with Reflex to FISH (Breast)

Additional Information:

If requested indeterminate results will be reflexed for Her2/neu FISH testing. A separate report will be issued.

CPT Code(s):

  • 88361
  • FISH Reflex: 88368 x 2

Specimen Requirements:

A paraffin block containing representative breast tumors

Fixation: 10% formalin

Storage/Transport: Ship specimens at 20° – 25° C to protect them from excessive heat. Include a surgical pathology report.

Unacceptable Conditions:
  • Frozen
Stability (collection to initiation of testing):
  • Ambient: Indefinitely


This test is used to determine if Herceptin therapy is warranted in invasive breast tumors. Interpretation of breast tumors is based on the 2007 ASCO/CAP guidelines. If requested, indeterminate results and triple negative cases can be reflexed for Her2Neu FISH testing. A separate report will be issued.


Immunohistochemistry and image quantitation using ACIS III


Immunohistochemistry is reported within 7 days. If FISH is required and requested, the additional report will be provided within an additional 2 – 7 days.

Reference Values:

  • 0.0 – 1.7 Negative: No staining or weak, incomplete membrane staining in any portion of the invasive tumor or weak complete membrane staining in less than 10% of the cells
  • 1.8 – 2.9 Indeterminate: Complete membrane staining that is non-uniform or weak but with obvious circumferential distribution in at least 10% of the tumor cells; or intense complete staining in 305 or less of the tumor cells
  • ≥ 3.0 Positive: Uniform intense membrane staining of more than 30% of invasive tumor

Interpretation Data:

Breast: The HercepTest is interpreted using quantitative analysis using the DAKO ACIS III instrument. The assay is performed on paraffin-embedded tissue using the FDA-approved staining method (polyclonal antibody and LSAB detection system).