FISH, PDGFRB, 5q33.1, TC

Test Code

12649

CPT Codes
88271 (x2), 88275<br>Restricted Client Code - Tech Only

Preferred Specimen

3 mL bone marrow collected in a sodium heparin (green-top) tube or
5 mL whole blood collected in a sodium heparin (green-top) tube

Minimum Volume

3 mL whole blood
1 mL bone marrow

Other Acceptable Specimens

Bone marrow or whole blood collected in a sodium heparin (royal blue-top) tube or sodium heparin lead-free (tan-top) tube • 3 mL bone marrow in transport medium • 5x5 mm fresh tumor tissue collected in transport medium • Formalin-fixed, paraffin-embedded tissue block

Instructions

Clinical history and reason for referral are required with test order. Prior therapy and transplant history should be provided with test order.

1-3 mL bone marrow in transport medium or 3-5 mL whole blood in a sodium heparin tube (green top, royal blue top, tan top).
Formalin fixed paraffin embedded tumor biopsy or 5 mm x 5 mm fresh tumor biopsy in transport medium.

Specimen viability decreases during transit. Send specimen to testing lab for viability determination. Do not freeze. Do not reject.

Transport Temperature

Room temperature

Specimen Stability

See Instructions

Methodology
Fluorescence in situ Hybridization (FISH)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Set up: Daily; Report available: 5 days

Clinical Significance

100-300 interphase cells are microscopically analyzed for probe signal patterns indicating rearrangement of 5q33.1. FISH testing with the PDGFRB probe allows detection of translocations involving PDGFRB and another chromosome region (usually a tyrosine kinase coding gene). Fusion of PDGFRB with a tyrosine kinase coding gene leads to kinase activation.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.