Test Overview
Test Methodology

Interphase Fluorescence In Situ Hybridization (FISH)

Test Usage

Rearrangements of PDGFRA, PDGFRB, FGFR1 and PCM1-JAK2 are found in a rare group of stem cell myeloid and lymphoid neoplasms that have in common the presence of eosinophilia and the involvement of genes that code for a tyrosine kinase. This FISH panel aids in diagnosis and classification of hematopoietic neoplasms presenting with prominent eosinophilia. It includes probes that target the PDGFRA (4q12 tricolor rearrangement probe), PDGFRB (5q33.1 break apart probe), FGFR1 (8p11 break apart probe), and JAK2 (9p24 break apart probe) loci. Detection of these rearrangements will help to properly diagnose and treat these patients. Furthermore, patients with activated tyrosine kinases are good candidates for tyrosine kinase inhibitors.

Reference Range *

Interpretive report provided.

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

Test Details
Days Set Up
Monday - Friday, 8:00am - 4:00pm
Soft Order Code
CGEOS
MiChart Code
Cytogenetics, Eosinophila FISH Panel
Laboratory
Cytogenetics
Section
Cytogenetics
Specimen Requirements
Collection Instructions

Specimen transport should be arranged so that the specimen is received by MLabs the same day it is collected. Call for a STAT courier if necessary. Collect specimen in a green top (sodium heparin) tube. Invert the tube several times to prevent clotting. Send at room temperature as soon as possible. Do not allow specimen to overheat or freeze. Clotted samples or those that are greater than 24 hours old are suboptimal. Eosinophilia FISH panel testing may be performed as a "stand alone" test or included with Chromosome Analysis.

Normal Volume
5 mL whole blood (with >10% involvement) or 2 mL bone marrow
Minimum Volume
2 mL whole blood (with >10% involvement) or 1 mL bone marrow
Rejection Criteria
Clotted or hemolyzed specimen, specimen over 24 hours old, or those from septic or transfused patients.
Additional Information

"Stand alone" FISH testing will include Tissue Culture at an additional charge.

Billing
CPT Code
88237, 88271 x4, 88275 x4
Fee Code
36542, EA040 x4, EA041 x4