Atypical immunophenotype of chronic lymphocytic leukemia

Abstract

Assessment of the immunophenotype plays a crucial role in the diagnostic process of chronic lymphocytic leukemia (CLL). The expression of CD5, CD19 and CD23 antigens with a concomitant reduction or lack of surface immunoglobulin expression as well as CD22 and CD79b antigens is the basic part of CLL diagnosis. A significant diagnostic challenge is atypical CLL with cells devoid of CD5 or CD23 antigens. The assessment of additional antigens in flow cytometry, especially the CD200 glycoprotein, may facilitate the process of differential diagnosis of atypical CLL from other B-cell lymphoproliferative neoplasms. The results of current studies analyzing the influence of atypical CLL on prognosis are inconclusive. The analysis of a large group of patients with atypical CLL is difficult because of the rare occurrence of CD5(-) or CD23(-) CLL and the misdiagnosis of this disease as other B-cell lymphoproliferative neoplasms.The following paper aims to show how important it is to include atypical CLL in the diagnostic process of this disease and to re-standardize the commonly used immunophenotypic scales for its diagnosis.

CD5‐negative chronic lymphocytic leukemia: Does this entity really exist?

“…Nevertheless, it appears that the current state of global laboratory practice for the diagnosis of CLL does not follow this position, as the label "CD5-negative chronic lymphocytic leukemia" is still being used in the practice of hematologists, and cited in recent scientific publications, giving the false impression that there are sufficient data to unquestionably establish this diagnosis (Albakr et al, 2018;Basabaeen et al, 2022;Batata & Shen, 1992;Cartron et al, 1998;Chen et al, 2019;Criel et al, 1994Criel et al, , 1999De Rossi et al, 1993;Demir et al, 2017;Deneys et al, 2001;Döhner et al, 2000;Efstathiou et al, 2002;Faguet et al, 1992;Geisler et al, 1991;Huang et al, 1999;Hwang et al, 2009;Ikematsu et al, 1994;Ivancevi c et al, 2014;Keung et al, 2002;Kim et al, 1999;Kurec et al, 1992;Lennert et al, 1991;Li et al, 2021;Maloum et al, 1995Maloum et al, , 1997Matutes et al, 1996;Morice et al, 2008;Myles et al, 2021;Que et al, 1993;Rawstron et al, 2016;Salomon-Nguyen et al, 1995;Shapiro et al, 1999;Sheikh et al, 2002;Specchia et al, 2002;Urbaniak et al, 2022;Yamada et al, 1995;Yan et al, 2020).…”

Atypical Chronic Lymphocytic Leukemia—The Current Status

“…The typical immunophenotype includes the coexistence of CD19, CD20, CD5, and CD23 antigens on leukemic cells ( Figure 3 ). While CLL can be accurately diagnosed using flow cytometry in the majority of patients, such a diagnosis becomes more challenging when CD23 or CD5 is not expressed by the leukemic cells [ 18 , 29 , 35 , 36 , 37 , 38 , 39 ]. In clinical practice, in cases lacking CD5 or CD23, the diagnostic process begins with confirming or rejecting aCLL.…”

correlation between CD200 expression and oxidant-antioxidant status in newly diagnosed B-chronic lymphocytic leukemia patients

“…No pathognomonic factor that allows us to identify a diagnosis has been identified yet. Additionally, efforts will continue to develop an international agreement regarding the essential markers for diagnosing CLL [20][21][22]. Consequently, immunophenotyping profile changes can be effective in predicting clinical course, patient survival, and determining first line therapy.…”