FISH ANALYSIS, PML/RARA TRANSLOCATION
Pseudonyms: t(15;17); 15;17 Translocation; PML-RARA Translocation; PML/RARA Fusion; PML-RARα Translocation; PML-RARα Fusion; Acute Promyelocytic Leukemia; APL; AML M3
TURNAROUND TIME: 2 days for diagnostic sample. 10 days for minimal residual disease assessment.
TESTING METHODOLOGY: Fluorescence in situ hybridization
- Collect: 2 mL bone marrow aspirate in sodium heparin (green); 5 mL peripheral blood in sodium heparin (green) also acceptable
- Minimum Collection: 1 mL bone marrow or 2 mL peripheral blood
- Transport: bone marrow or peripheral blood in sodium heparin (green) at 20-25°C; specimen should arrive in the laboratory within 24 hours of collection
- Stability: Ambient: 24 hours; Refrigerated: 24 hours; Frozen: unacceptable
- Unacceptable Conditions: Frozen or clotted specimens; paraffin-embedded specimens; specimens in anticoagulants other than sodium heparin.
Test Summary: Test can detect the 15;17 translocation characteristic of acute promyelocytic leukemia (APL); for diagnostic specimens, it is recommended that test be performed with chromosome analysis
Methods: A dual-color dual-fusion FISH analysis performed on interphase cells using a probe for the PML gene on chromosome 15q22 and a probe for the RAR-alpha gene on chromosome 17q21; analysis of 200 interphase cells; analysis of 500 interphase cells for minimal residual disease assessment
Interpretation: A positive result (PML-RARA fusion) is reported when the percent of cells with an abnormality exceeds the normal reference range for the probes. The detection of an abnormal clone indicates a diagnosis of APL with the 15;17 translocation. A negative result indicates no 15;17 translocation was observed but does not rule out the presence of a neoplastic disorder.
FDA Approval: This test is not approved by the FDA and it should be used as an adjunct to clinical and pathological information.
Indications for Use:
- Establishing the diagnosis of APL
- Monitoring the 15;17 translocation (PML-RARA fusion) during treatment
- Detecting residual disease in patients with the 15;17 translocation