Hematologic Diseases

Rearrangements of the PDGFRa (4q12), PDGFRb (5q32), FGFR1 (8p11), JAK2 (9p24.1) genes are detected by fluorescence in situ hybridization (FISH).

disease state indication(s)
Myeloid/lymphoid neoplasms with eosinophilia, chronic eosinophilic leukemia (CEL)

clinical use
Myeloid/lymphoid neoplasms with eosinophilia and rearrangement of PDGFRA, PDGFRB, or FGFR1, or with PCM1-JAK2 are disease entities in the World Health Organization (WHO) classification of hematopoietic tumors that are characterized by eosinophilia and variable response to tyrosine kinase inhibitors (TKI). PDGFRA and PDGFRB rearrangements are associated with an increased likelihood of response to TKI. FGFR1 rearrangement is associated with an unfavorable prognosis, and there is currently no established TKI for neoplasms with this rearrangement.

methodology/product platform
Fluorescence in situ hybridization (FISH)

specimen type and requirements
Peripheral blood: 5-6 mL in sodium heparin (green-top) tube.
Bone marrow: 2-3 mL in sodium heparin (green-top) tube.
Bodily fluids: Bodily fluids for diagnostic testing of hematological cancers (subject to specimen viability). Preferred transport in equal parts RPMI.
Lymphoid tissue: Transport in RPMI.
Note: Use refrigerated cold pack for transport. Make sure cold pack is not in direct contact with specimen.

Probe Prioritization: If samples are insufficient to complete the whole FISH panel, Genoptix will prioritize testing in the following order: PDGFRα, PDGFRβ, FGFR1, and JAK2, unless directed otherwise by the client.

turnaround time
Tech-only (TC): 3 days
Global (TC & PC): 5 days

cpt code(s)
88377 (x4)

medicare moldx cpt code
Not applicable

regulatory classification
Laboratory developed test (LDT)

ordering option
Global (TC & PC) or Tech-only (TC)