Probes: BCL6 (3q27) | MYC (8q24) | BCL2 (18q21) | MYC/IgH/CEN8 t(8;14)
Optional Reflex: IGK/MYC t(2;8) | IGL/MYC t(8;22) | BCL6/MYC t(3;8), if MYC (8q24) is positive and MYC/IgH/CEN8 t(8;14) is negative
Disease(s): B-cell lymphoma, double-hit lymphoma, triple-hit lymphoma
This panel differentiates double-hit or triple-hit lymphomas (which have MYC rearrangements together with BCL2 and/or BCL6 rearrangements) from Burkitt lymphoma or diffuse large B-cell lymphoma. Double-hit and triple-hit lymphomas are difficult to classify morphologically without aid of cytogenetics/FISH or IHC, and are associated with an aggressive course. Testing is indicated when B-cell lymphoma patients experience transformation, relapse, or refractory disease. MYC rearranges with an immunoglobulin partner in approximately 60% of MYC-rearranged DLBCL/HGBCL of which 75% are MYC/IgH fusion. MYC/IgH/CEN8 will confirm heavy chain rearrangement when MYC is rearranged.
IGK/MYC t(2;8), IGL/MYC t(8;22) and BCL6/MYC t(3;8) studies are useful to further subclassify lymphomas that are positive for MYC gene rearrangements, but negative for the most common IGH/MYC translocation. In addition, when both MYC and BCL6 gene rearrangements are present, but no IGH/MYC translocation is identified, these studies may help to differentiate between the double-hit/triple-hit lymphomas (D/T-HL), which have a poor prognosis, and DLBCL with BCL6/IGH translocation, representing a subset of GC B-cell lymphomas distinct from conventional D/T-HL and with better prognosis (so-called "pseudo-double-hit lymphoma").
Clients may want to consider the High-Grade B-Cell Lymphoma Reflex FISH Panel as a cost-effective alternative.
- Bone marrow aspirate: 1-2 mL sodium heparin tube. EDTA tube is acceptable.
- Peripheral blood: 2-5 mL sodium heparin tube. EDTA tube is acceptable.
- Fresh, unfixed tissue: Tissue in RPMI.
- Bone Marrow/ Peripheral Blood Smear or Fresh Tissue Touch Preparation Slides: minimum *3-5 slides* labeled with specimen type.
- NOTE: 3 slides needed for base 3 probe panel, 1 slide needed if optional 14;18 added, 1 slide needed if optional 8;14 added
- Fluids: Equal parts RPMI to specimen volume
- Fixed Cell Suspension: A client fixed cell suspension may be submitted for testing as long as it is received in 3:1 Methanol:Glacial Acetic Acid.
- Paraffin block: H&E slide (required) plus paraffin block. Circle H&E for tech-only.
- Cut slides: H&E slide (required) plus 8 unstained slides cut at 4 microns. Circle H&E for tech-only.
- Note: Please exclude biopsy needles, blades, and other foreign objects from transport tubes. These can compromise specimen viability and yield, and create hazards for employees.
Refrigerate fresh specimens. Do not freeze. Use cold pack for transport, making sure cold pack is not in direct contact with specimen. For fresh samples: ship same day as drawn whenever possible; specimens <72 hours old preferred.
3-5 days for both unfixed and FFPE specimens