1p/19q Deletion by FISH
Also known as: 1P19Q_FISH
Use
This test is crucial for diagnosing oligodendroglioma brain tumors, applicable for both low-grade and high-grade (anaplastic) oligodendrogliomas. The codeletion of 1p and 19q, resulting from an unbalanced translocation, is a hallmark of oligodendrogliomas and is considered a diagnostic feature according to the WHO Classification of Tumours of the Central Nervous System. Furthermore, the codeletion predicts a favorable response to combination chemotherapy. Isolated deletions of 1p or 19q alone do not provide diagnostic or predictive value.
Special Instructions
Include a surgical pathology report with the specimen. Use ARUP’s tissue transport kit if available for paraffin blocks or slides, and provide order comments if multiple specimens are sent to ensure ARUP pathologists choose the most appropriate specimen for testing. Orders utilizing the Pathologist Block Selection option incur an additional fee.
Limitations
This test was developed for clinical purposes and its performance is characterized by ARUP Laboratories. It is not FDA-cleared or approved. The test has a 96% detection rate for 1p and 19q deletions in oligodendroglioma patients. However, it is crucial to correlate results with histopathological findings and other laboratory data for optimal risk stratification. Polysomy of chromosomes 1 and/or 19 might indicate a less favorable prognosis.
New York Approved
Methodology
Chromosomal / Cytogenetics (FISH)
Biomarkers
LOINC Codes
- 42634-6
- 81304-8
- 78236-7
Result Turnaround Time
3-7 days
Related Documents
For more information, please review the documents below
Specimen
Tumor Tissue (FFPE)
Volume
Not provided
Minimum Volume
Not provided
Container
Tissue transport kit (ARUP supply #47808)
Collection Instructions
Formalin fix (10 percent neutral buffered formalin) and paraffin embed tissue. Protect paraffin block from excessive heat. Transport block or 6 unstained (4 micron thick sections) positively charged slides.
Storage Instructions
Room temperature or refrigerated; ship in cooled container during summer months.
Causes for Rejection
Paraffin block with no tumor tissue remaining. Specimens fixed in any fixative other than 10 percent neutral buffered formalin. Decalcified specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Indefinitely |
| Refrigerated | Indefinitely |
| Frozen | Unacceptable |