EWSR1 (22q12) Gene Rearrangement by FISH
Also known as: EWSR1_FISH
Use
This test is used to diagnose members of the Ewing sarcoma family of tumors (ESFT) by detecting rearrangements involving the EWSR1 gene. However, it does not identify specific translocation partner genes. EWSR1 rearrangements are useful markers for diagnosing Ewing family of tumors and are also found in other tumors including clear cell sarcoma, desmoplastic small round cell tumor, extraskeletal myxoid chondrosarcoma, myxoid liposarcoma, rhabdomyosarcoma, and angiomatoid fibrous histiocytoma. Thus, correlation with histopathologic and clinical findings is essential for complete interpretation.
Special Instructions
Not provided.
Limitations
This test can detect EWSR1 gene rearrangements in patients with EWSR1 rearranged tumors but cannot identify the translocation partner. The assay does not detect very rare cryptic rearrangements. An abnormal signal pattern in 25% or more of tumor cells is considered positive. No approvals from U.S. Food and Drug Administration but performed in a CLIA-certified laboratory for clinical purposes.
New York Approved
Methodology
Chromosomal / Cytogenetics (FISH)
Biomarkers
No genes
Gene
LOINC Codes
- 81304-8 - Struct var analysis method
- 78236-7 - Cells.IGH rear/Cells cnt NFr Bld/T FISH
Result Turnaround Time
3-7 days
Related Documents
For more information, please review the documents below
Specimen
Tissue (FFPE)
Volume
Not provided
Minimum Volume
2 slides
Container
tissue transport kit
Collection Instructions
Paraffin block with tumor or 5 unstained slides.
Storage Instructions
Room temperature. Cool during summer.
Causes for Rejection
Paraffin block with no tumor tissue, non-formalin fixative, decalcified specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Indefinitely |
| Refrigerated | Indefinitely |
| Frozen | Unacceptable |
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