%0 Journal Article
%T Clinical Features and Prognosis of CD20 Negative Aggressive B-Cell Non-Hodgkins Lymphoma
%A Sumit Gaur
%A Osvaldo Padilla
%A Zeina Nahleh
%J Lymphoma
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/290585
%X Cluster designation (CD) 20 antigen is expressed on most B-cell lymphomas and serves as a therapeutic target for rituximab. A small minority of aggressive B-cell lymphomas, predominantly plasmablastic variants, do not express CD 20. We systematically reviewed all cases of aggressive B-cell lymphomas diagnosed at our institution over a period of 13 years. Of the 232 cases, 7 did not express CD 20. Five of these were plasmablastic lymphomas while two were unclassifiable B-cell lymphomas. While most of the plasmablastic lymphomas responded to chemotherapy, patients with unclassifiable lymphomas were primarily refractory or relapsed soon after chemotherapy. 1. Introduction Diffuse large B cell lymphoma (DLBCL) is the most common histological subtype of non-Hodgkin¡¯s lymphoma in adults [1]. The addition of rituximab, a chimeric monoclonal antibody, to standard chemotherapy represents the most significant advance in the therapy of DLBCL over the last decade [2, 3]. Rituximab is directed against CD (cluster designation) 20, a cell surface glycoprotein, expressed on the surface of most B cells [4]. Identification of CD 20 expression thus aids in identifying the lymphoma as being of B-cell origin and in being potentially susceptible to rituximab. A small minority of DLBCL do not express CD 20. Most of these are reported to be plasmablastic variants of DLBCL (primary effusion lymphomas, Anaplastic lymphoma kinase positive large B-cell lymphoma, and human immunodeficiency-virus associated plasmablastic lymphoma) and have been reported to have worse outcomes compared to other DLBCL [5¨C7]. We systematically reviewed the clinical and pathological features of all CD 20 negative DLBCL lymphoma patients diagnosed at our institution over the last 13 years. 2. Methods The study received a waiver from the institutional review board for review of archival material and patient charts. All patients diagnosed with diffuse large B-cell lymphoma from January 1, 1998 to June 31, 2011 were identified through the tumor registry. Pathological and immunophenotypic findings were reviewed to identify patients with CD 20 negative DLBCL. All microscopic slides from these cases, including hematoxylin & eosin and immunohistochemical stains were reviewed by the authors. Results of cytogenetic, fluorescent in situ hybridization (FISH) probes and polymerase chain reaction (PCR) analysis were reviewed when available. After confirming a diagnosis of CD 20 negative large B-cell lymphoma, we extracted the following clinical characteristics from the patient¡¯s medical records: age, sex, race, HIV
%U http://www.hindawi.com/journals/lymph/2013/290585/