The Significance of Lacking Surface Immunoglobulin Light Chain Expression in B-Cells by Flow Cytometry.
Alireza Zarineh, Samiah Zafar, Thaira Oweity, Jonathan Harris, Sherif Ibrahim, Cynthia Liu. New York University, NY
Background: The value of flow cytometry in the diagnosis of B-cell lymphomas frequently rests upon the ability to demonstrate surface immunoglobulin kappa or lambda light chain restriction, which demonstrates B-cell clonality. Often abnormal B-cell populations are detected which do not express surface kappa or lambda light chains, a common finding recognized in large B-cell lymphomas. We reviewed our flow cytometry cases which had a B-cell population lacking surface light chains in order to determine the significance of such finding in regards to subsequent follow-up data.
Design: This study consists of forty flow cytometry cases reported as having a B-cell population lacking surface immunoglobulin light chain expression from 40 patients over a 3-year period at a tertiary care hospital. Methods of specimen collection included 22 fine needle aspirates (FNA), 7 excisional tissue samples, 8 pleural fluid and 3 peripheral blood.
Results: The follow-up data were available from histology (n=27), and cytologic diagnosis and/or molecular studies (n=13). Upon follow-up review, only 20/40 cases (50%) showed a lymphoma with diffuse large B-cell lymphoma as the leading group (11/20) (See Table).
|Diffuse large B cell lymphoma||11|
|Marginal zone lymphoma||1|
|Mediastinal large B cell lymphoma||1|
|Chronic lymphocytic leukemia||1|
|Nodular lymphocyte predominant Hodgkin lymphoma||1|
|B-cell non-Hodgkin lymphoma, not further specified||2|
|Atypical lymphoid proliferation||3|
|Negative for lymphoma (morphologic and/or molecular diagnosis)||12|