Test Directory

• ABL1, 9q34.11-q34.12
• ASS1, 9q34.11-q34.12
• BCR, 22q11.22-q11.23

Chronic myelogenous leukemia (CML) is a stem cell disorder characterized by the cytogenetic abnormality of t(9;22)(q34;q11.2), which progresses from a chronic phase to an accelerated phase, and/or a blast phase of myelocytic or lymphoid phenotype. This progression is frequently preceded or accompanied by recurring secondary chromosomal abnormalities. The abnormality, t(9;22)(q34;q11) has been identified in 84% of typical CML, 13% acute lymphoblastic leukemia (ALL), 1% acute myeloid leukemia (AML) and 2% myelodysplastic syndrome (MDS). Philadelphia chromosome-positive acute myeloid leukemia (Ph+ AMLs) are increasingly being reported with either major breakpoint cluster region (M-BCR) or minor breakpoint cluster region (m-BCR) gene rearrangements, similar to those found with philadelphia chromosome-positve acute lymphocytic leukemia (Ph+ ALL) lending support to the notion that Ph+ AML are distinct entities and not merely blastic phases of undiagnosed CML. This is further supported by the existence of philadelphia chromosome-positive myelodysplastic syndrome (Ph+ MDS) cases. Additional abnormalities are: +der(22), +8, i(17q), +19, most often, but also: +21, -Y, -7, -17, +17; acute transformation can also be accompanied with t(3;21) (q26;q22) (1% of cases). FISH can detect this translocation in either interphase or metaphase cells.

Specimen Types: Leukemic Blood or Bone Marrow

Preferred Collection Container: Green Top (Sodium Heparin)

Alternate Collection Container: Lavendar Top (EDTA)

Desired Specimen Volume: 3 - 5 mL

Minimum Acceptable Volume: 1 mL

• Lithium heparin is not acceptable.
• Specimens must be collected in a sterile collection container.

Each specimen must be accompanied by a requisition form, script, electronic order or physician note. Each order must indicate the reason for testing (diagnosis).

• Transport to the laboratory at room temperature.
• Store specimen as whole blood, in original tube, at room temperature and deliver to lab within 24 hours.
• If specimen cannot be delivered within 24 hours, store in refrigerator. Do not freeze specimen.
• Specimens collected on the weekends must be refrigerated upon arrival at HNL Lab Medicine.

• Specimen frozen
• Specimen arriving without any form of patient identification (unlabeled)
• Specimen with attached needles
• Specimen arriving with broken or leaking collection tube
• Unfixed specimen treated with fixative

In a normal cell, the expected signal pattern is two red signals, two aqua signals, and two green signals. In an abnormal cell containing a typical translocation, the expected signal pattern is one red signal, two aqua signal, one green signal, an aqua/red/green der(9) fusion signal, and a red/green der(22) fusion signal.

• FISH CML
• Chronic Myeloid Leukemia
• BCR-ABL
• t(9;22)
• Breakpoint Cluster Region