Effective February 3, 2021, MLabs will offer High Grade B-Cell Lymphoma (CGLMP) testing.
Test Usage: 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 the 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. In addition, a small subset of lymphomas with MYC rearrangement (4%) may be missed when using the MYC breakapart probe alone, but some of these cases may be detected using the MYC/IGH fusion probe set (PMID: 30523057). The FISH panel for high grade B-cell lymphoma includes MYC (8q24), IGH/MYC/CEN8 [t(8;14)], BCL2 (18q21) and BCL6 (3q27) translocations.
Collection Instructions: Collect bone marrow using aseptic technique. Place 1 - 5 mL bone marrow aspirate in a green top (sodium heparin) tube. Invert the tube several times to prevent clotting. Send at room temperature as soon as possible. Do not allow specimen to overheat or freeze. Clotted samples, samples containing <5 million dividing cells, and samples that are greater than 24 hours old are suboptimal.
Methodology: Fluorescence in situ hybridization (FISH)
Analytic Time: 7 days
Reference Range: Interpretive Report