FISH ANALYSIS, ACUTE LYMPHOCYTIC LEUKEMIA (ALL) PROFILE, ADULT
Pseudonyms: B-cell Acute Lymphocytic Leukemia, B-cell ALL, ALL
TURNAROUND TIME: 7 to 10 days
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: Probes included: BCR/ABL, MLL and IGH
Methods: A dual-color, dual-fusion FISH analysis performed on interphase cells using a probe for the BCR gene on chromosome 22q11.2 and a probe for the ABL1 gene on chromosome 9q34; analysis of 200 interphase cells; analysis of 500 interphase cells for minimal residual disease assessment.
A dual-color, break-apart FISH analysis performed on interphase cells using probes for 5' and 3' ends of the MLL gene on chromosome 11q23; analysis of 200 interphase cells; analysis of 500 interphase cells for minimal residual disease assessment.
A dual-color, break-apart FISH analysis performed on interphase cells using probes for 5' and 3' ends of the IGH gene on chromosome 14q32; analysis of 200 interphase cells; analysis of 500 interphase cells for minimal residual disease assessment.
Interpretation: A positive result 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 B-cell ALL with the specific chromosome abnormality. A negative result indicates no abnormality was observed but does not rule out the presence of a neoplastic disorder.
Reference Values: An interpretive report is provided for each probe set.
FDA Approval: This test is not approved by the FDA and it should used as an adjunct to other clinical and pathological information.
Indications for Use:
- Patients with B-cell ALL; establishing the percentage of neoplastic cells at diagnosis.
- Identifying patients with B-cell ALL who have a 9;22 translocation, rearrangement of the MLL gene or rearrangement of the IGH gene.
- Provide prognostic indicators for patients with B-cell ALL.
- Evaluate specimens in which standard cytogenetic analysis is unsuccessful or results are normal.