[1290] A Novel Flow Cytometric Antibody Panel for Distinguishing Burkitt Lymphoma from CD10-Positive Diffuse Large B-Cell Lymphoma

SD Schniederjan, S Li, MJ Lechowicz, DF Saxe, PD Terry, KP Mann. Emory University School of Medicine, Atlanta; Winship Cancer Institute, Emory University School of Medicine, Atlanta; Rollins School of Public Health, Emory University, Atlanta

Background: Rapid and accurate differential diagnosis between Burkitt lymphoma (BL) and CD10+ diffuse large B-cell lymphoma (CD10+ DLBCL) is imperative as their treatment differs. Undertreatment of BL results in treatment failure, whereas overtreatment of DLBCL adds toxicity without improving response rate or survival. Distinguishing BL from CD10+ DLBCL can be problematic, especially in cases with minimal material for evaluation. Recent studies have characterized several antigens differentially expressed in these two types of lymphoma. Our goal was to determine whether use of these markers would aid in the differential diagnosis of BL versus CD10+ DLBCL by flow cytometric immunophenotyping (FCI).
Design: Twenty-five cases of CD10+ B-cell lymphomas with available cryopreserved samples were identified (15 cases of BL with confirmed MYC gene rearrangements and 10 CD10+ DLBCL). Four normal controls, 10 cases of low grade follicular lymphoma, 3 cases of precursor B-cell acute lymphoblastic leukemia, and 3 cases of high grade B-cell lymphoma (not further characterized) were also analyzed. Samples were thawed and multiparameter FCI was performed using the following antibodies: CD18, CD20, CD43, CD44, CD54, and isotype controls. The difference between mean fluorescence intensity (channel values) and isotype controls was calculated for each antibody. Two-tailed T tests were performed comparing antigen expression between BL and CD10+ DLBCL.
Results: Expression of CD44 and CD54 was detected at a significantly lower level in BL as compared to CD10+ DLBCL (p=0.01 and p=0.005, respectively). There was not a significant difference in expression of CD18 and CD43 (p=0.38 and p=0.40, respectively).
Conclusions: Distinguishing between BL and CD10+ DLBCL is imperative to rapidly initiate appropriate therapy. Our data shows that expression of CD44 and CD54 differs significantly between these lymphomas. Therefore, a flow cytometric immunophenotypic panel including these antibodies may prove valuable for differential diagnosis of CD10+ B-cell lymphomas. Prospective studies are necessary to confirm that using these markers, in conjunction with routine antigen analysis, will allow differential diagnosis of these two entities.
Category: Hematopathology

Wednesday, March 11, 2009 9:30 AM

Poster Session V # 173, Wednesday Morning