Test Overview
Test Methodology

Fluorescence In Situ Hybridization (FISH)

Test Usage

NR4A3 encodes an orphan nuclear receptor. Rearrangements of NR4A3 occur in more than 80% of extraskeletal myxoid chondrosarcoma (EMC) as well as in salivary acinic cell carcinoma (AciCC), driving tumorigenesis. With EMC, NR4A3 rearrangements fuse the 3’ end of NR4A3, including its DNA binding domain, to a variety of 5’ oncogenic transcription activator fusion partners. With AciCC, NR4A3 rearrangement translocates highly active chromatin regions to the upstream region of NR4A3. The detection of NR4A3 rearrangements can be useful in diagnosing EMC and AciCC – including uncommon histologic variants – and in distinguishing these neoplasms from other myxoid neoplasms and salivary gland tumors, respectively.

Reference Range *

Interpretive report provided.

*Reference ranges may change over time. Please refer to the original patient report when evaluating results.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Limitations

This test will detect rearrangements involving NR4A3 but will not identify the translocation partner. The test may fail to detect NR4A3 rearrangements involving a submicroscopic insertion or with a breakpoint outside of the region interrogated by the probes used in this assay.

Test Details
Days Set Up
Monday – Thursday
Analytic Time

3 – 10 days

Soft Order Code
MiChart Code
NR4A3 (9q22-9q31) Rearrangement by FISH
Molecular Diagnostics
Molecular Diagnostics
Specimen Requirements
Collection Instructions

A formalin-fixed, paraffin-embedded tissue block (containing sufficient neoplastic cells) is preferred. Unstained slides (3 slides cut at 4-microns) with associated H&E-stained slide are also acceptable. Decalcified tissue or tissues with other fixatives will be accepted and the assay attempted; however, these specimens may result in failed testing due to degraded nucleic acid. Both blocks and slides should be stored at room temperature.

Normal Volume
Formalin-fixed, paraffin-embedded tissue
Additional Information

By ordering this test the clinician acknowledges that informed consent has been obtained from the patient as required by applicable state or federal laws and the ordering clinician has authorization from the patient permitting MLabs to report the test results to the ordering clinician. Test includes pathologist interpretation of results billed as a separate additional charge. This test is not available without interpretation.

CPT Code
Fee Code
Pro Fee CPT