Karyotyping (when bone marrow is infiltrated);
Fluorescence in situ hybridisation on FFPE tissue sections, FNA's, cytospins:
IGH-MYC to detect t(8;14); MYC (8q24) to detect variant rearrangements;
IGH-CCND1 to detect t(11;14);
IGH-BCL2 to detect t(14;18);
A number of cytogenetic abnormalities are specific to certain sub-types of non-Hodgkin's lymhoma (NHL) and as such can be very useful in aiding diagnosis, particularly where histopathology and immunophenotyping is ambiguous. The detection of MYC abnormalities can be especially critical in optimising therapy, where a confirmed diagnosis of Burkitt lymphoma (BL) determines a very disease-specific treatment regimen. MYC abnormalities are also detected in diffuse large B-cell lymhoma (DLBCL) and in B-cell lymphoma, unclassifiable, with features intermediate between DLBCL and BL (intermediate BL/DLBCL), and this has been shown to be an adverse prognsotic risk factor in patients treated with R-CHOP. MYC rearangements can also be detected along with BCL2 and/or BCL6 rearrangements, especially in intermediate BL/DLBCL, identifying the so-called double hit lymphomas which are associated with a particularly aggressive clinical course. Analysis of NHL's lends itself particularly well to interphase FISH analysis of formalin-fixed paraffin-embedded (FFPE) tissue sections, where close corrleation with H&E and/or immunohistochemistry (IHC) slides enables the analysis of small focal tumour infiltrates and removes the risk of false negative results arising from analysis of non-malignant cells.
Synonyms or keywords:
IGH-MYC, t(8;14), high grade B-cell NHL, low grade B-cell NHL, diffuse large B-cell lymphoma, DLBCL, Burkitt, BL, MCL, mantle cell, Follicular, FL, MALT, MALToma, IGH-CCND1, t(11;14), IGH-BCL2, t(14;18), ALK, Anaplastic, BCL6, MALT1, IGH-MALT1, API2-MALT1, MYC