Aid in prediction of response to HER2-directed therapy in patients with breast carcinoma or gastroesophageal adenocarcinoma. Use to confirm equivocal HercepTest (2+) immunohistochemistry (IHC) result.
Fluorescence in situ Hybridization (FISH)
Formalin fix (10 percent neutral buffered formalin) and paraffin-embed tissue. Fixative duration: 6-72 hours. Protect paraffin block from excessive heat. Transport block or 7 unstained (4 micron thick sections) positively charged slides in a tissue transport kit (ARUP supply #47808) available online through eSupply using ARUP Connect™ or contact ARUP Client Services at (800) 522-2787 (kit recommended but not necessary). (Min 4 slides)
Room temperature. Also acceptable: Refrigerated. Ship in cooled container during summer months.
Specimens fixed or processed in alternative fixatives (alcohol, Prefer) or heavy metal fixatives (B-4 or B-5). No tumor in tissue. Decalcified specimens. Tissue fixed for less than 6 hours or greater than 72 hours.
Include surgical pathology report.
If multiple specimens (blocks or slides) are sent to ARUP, they must be accompanied by one of the following: an order comment indicating that the ARUP pathologist should choose the specimen most appropriate for testing (e.g., "Choose best block"), or individual orders for each sample submitted. A Pathologist Block Selection Fee (ARUP test code 3002076) will be added to orders that utilize the first option. If multiple specimens are sent to ARUP without a request for pathologist block/slide selection or individual orders, they will be held until clarification is provided.
Ambient: Indefinitely; Refrigerated: Indefinitely; Frozen: Unacceptable
Refer to report. ARUP uses the most recent ASCO/CAP interpretation criteria for evaluating ERBB2 (HER2) status.
Breast tissue results of FISH group 2, 3, or 4 will be reflexed to ERBB2 (HER2/neu) (HercepTest) with Interpretation by Immunohistochemistry, Tissue (ARUP test code 0049174). Additional charges apply. Gastric and other non-breast tissue with indeterminate results will be reflexed to an alternate probe in an effort to resolve amplification status. Additional charges apply.
88377, if reflexed add 88360 or 88377
|Component Test Code*||Component Chart Name||LOINC|
|0049241||ERBB2 (HER2) by FISH||42783-1|
- c-erbB2 FISH
- ERRB2 FISH
- HER-2/neu FISH
- Her-2/neu Gene Amplification or Overexpression
- HER2/CEP17 Ratio