EGFR Gene Amplification by FISH

Casandra

Casandra Test Code AR55891Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 3001310CPT Code 88377

EGFR Gene Amplification by FISH

Also known as: EGFR_FISH

Clinical Use

Order Test

Use

This test aids in prognostication and therapeutic decisions for neoplasms where EGFR amplification has been demonstrated. It is not recommended for EGFR mutation detection in non-small cell lung carcinoma (NSCLC). EGFR gene amplification is often observed in various tumor types. In gliomas, its amplification is associated with higher-grade tumors, especially primary glioblastomas, correlating with worse outcomes in anaplastic astrocytoma. It may also be used as a prognostic marker or to predict tumor response to targeted therapy in other tumor types.

Special Instructions

Include the surgical pathology report. If multiple specimens (blocks or slides) are sent to ARUP, they must be accompanied by an order comment indicating that the ARUP pathologist should choose the most appropriate specimen for testing (e.g., 'Choose best block'), or individual orders for each sample must be submitted. A Pathologist Block Selection Fee (ARUP test code 3002076) will be added to orders that utilize the first option. Unacceptable specimens including paraffin blocks with no tumor tissue remaining.

Limitations

The test has not been cleared or approved by the US Food and Drug Administration. It is performed in a CLIA certified laboratory and is intended for clinical purposes. The test is performed on a section from a paraffin-embedded tissue block with fluorescent probes targeting the EGFR gene and chromosome 7 centromere (CEP7). It may not detect all forms of heterogeneity in tumors and does not identify EGFR mutations.

Test Details

New York Approved

Methodology

Chromosomal / Cytogenetics (FISH)

Biomarkers

No genes

Gene

EGFR/CEP7 FISH Ratio • Copy Number Alteration • Categorical (e.g., Positive / Negative / Indeterminate)

LOINC Codes

Result Codes

81304-8
78236-7

Result Turnaround Time

3-7 days

Specimen

Tumor Tissue (FFPE)

Volume

Not provided

Minimum Volume

2 slides

Container

Paraffin block or transport kit

Collection Instructions

Formalin fix (10 percent neutral buffered formalin) and paraffin embed tissue. Protect paraffin block from excessive heat. Transport tissue block or 5 unstained (4-micron thick sections) positively charged slides in a tissue transport kit.