BCR/ABL t(9;22),TEL/AML1 t(12;21), MLL(KMTA) 11q23
Acute lymphoblastic leukemia (ALL)
Fluorescence in situ Hybridization (FISH)
2.0 mL (min. 1.0 mL) peripheral blood in sodium heparin preferred, EDTA accepted
1.0 mL (min. 0.5 mL) bone marrow in sodium heparin preferred, EDTA accepted
Whole blood and bone marrow, ship ambient
Clotted specimen; Specimen exposed to extreme temperature; Anticoagulant toxic to cells; Insufficient number of cells;
Cytogenetic abnormalities occur in approximately 70% of adult ALL cases. Precursor B-cell acute lymphoblastic leukemia (ALL) occur in 85% of children and 20% of adults with acute leukemia. Abnormalities of chromosome number (hypodiploidy, hyperdiploidy) are more common in ALL than in AML. Hyperdiploidy in children with trisomies of chromosomes 4, 10 and 17 is associated with a good prognosis when structural anomalies are absent. Translocation (12;21) is very difficult to observe with conventional cytogenetic techniques. FISH can detect these abnormalities in interphase and metaphase cells.