“Double-Hit” Mature B-Cell Lymphomas Show a Common Immunophenotype by Flow Cytometry That Includes Decreased CD20 Expression

Abstract

Lymphomas with 2 translocations involving c-MYC and BCL2 or BCL6 are a subset of biologically aggressive mature B-cell lymphomas now frequently categorized under the entity of B-cell lymphoma, unclassifiable, with features intermediate between Burkitt lymphoma and diffuse large B-cell lymphoma. We identified a cohort of these lymphomas in our databases and retrospectively reviewed corresponding in-house flow cytometric data to determine whether a common immunophenotype might be present. Herein we report on our findings on 10 lymphomas, each with translocations involving c-MYC and BCL2 or BCL6 and show that these cases frequently showed a common immunophenotype that includes decreased expression of CD20. Because these lymphomas often show aggressive biologic behavior and poor clinical outcome, recognition of this relatively common immunophenotype may be useful for identifying cases for confirmatory cytogenetic studies, as often, flow cytometry provides the first assessment of these clinical specimens.

Diagnosis of ‘double hit’ diffuse large B-cell lymphoma and B-cell lymphoma, unclassifiable, with features intermediate between DLBCL and Burkitt lymphoma: when and how, FISH versus IHC

“…14,20,47 Flow cytometric demonstration of dim CD20 and/or dim CD19 to help identify DHL has also been reported, but others find it to be of limited utility because most cases do not have these features. [48][49][50] But what about the role of MYC IHC? It has been reported that finding Ն70% MYCϩ cells had a sensitivity of 100% and specificity of 93% for a MYC break.…”

BCL2 and MYC Dual-Hit Lymphoma/Leukemia

“…CD20 expression is positive in all cases of DHL, even if it is only weakly positive in a small population of cases. 19 Most DHL cases showed a molecular signature of IL 20 in gene expression profiling, although fewer cases more closely resemble BL. 21 The frequency of DHL with BCL2-IG and MYC translocation has been estimated at around 2% of all B-cell malignancies in a comprehensive manner.…”

Multimodality Technologies in the Assessment of Hematolymphoid Neoplasms

“…31 Burkitt lymphoma and aggressive B-cell lymphoma with MYC and BCL2 rearrangements (also called ''double-hit'' lymphoma) display some characteristic antigen expression profiles by flow cytometry that can be used in their differential diagnosis from DLBCL. 38,39 Furthermore, flow cytometry can provide prognostic and therapeutic information for patients with hematolymphoid neoplasms. For example, CD38 and ZAP70 are poor prognostic markers in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma.…”