Double-Expressor Phenotype (BCL-2/c-MYC Co-expression) of Diffuse Large B-Cell Lymphoma and Its Clinicopathological Correlation

Atif A Hashmi; Syeda N Iftikhar; Gul Nargus; Omer Ahmed; Ishaq Azeem Asghar; Umme Aiman Shirazi; Anoshia Afzal; Muhammad Irfan; Javaria Ali

doi:10.7759/cureus.13155

Double-Expressor Phenotype (BCL-2/c-MYC Co-expression) of Diffuse Large B-Cell Lymphoma and Its Clinicopathological Correlation

Cureus. 2021 Feb 5;13(2):e13155. doi: 10.7759/cureus.13155.

Authors

Atif A Hashmi¹, Syeda N Iftikhar¹, Gul Nargus², Omer Ahmed³, Ishaq Azeem Asghar⁴, Umme Aiman Shirazi¹, Anoshia Afzal⁵, Muhammad Irfan⁶, Javaria Ali¹

Affiliations

¹ Pathology, Liaquat National Hospital and Medical College, Karachi, PAK.
² Pathology, Khyber Medical College, Peshawar, PAK.
³ Internal Medicine, Liaquat National Hospital and Medical College, Karachi, PAK.
⁴ Pathology, Ascension St. John Hospital, Detroit, USA.
⁵ Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, USA.
⁶ Statistics, Liaquat National Hospital and Medical College, Karachi, PAK.

Abstract

Introduction Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease, the spectrum of which is increasing with time. The 2016 World Health Organization (WHO) update on hematopoietic tumors recognized a prognostic subgroup of DLBCL called double-expressor DLBCL. Double-expressor DLBCL is defined by the co-expression of c-MYC and BCL-2 by using immunohistochemical (IHC) studies. To our knowledge, very few studies have looked into the pathological features of this newly defined prognostic category of DLBCL; therefore, in this study we evaluated the frequency of the double-expressor phenotype of DLBCL and its association with other clinicopathological parameters. Methods We conducted a retrospective observational study in the Department of Histopathology, Liaquat National Hospital and Medical College, from November 2017 till December 2020. Pathological and clinical records were retrieved from departmental archives. All cases diagnosed as DLBCL were included in the study. More than 40% c-MYC expression in the presence of more than 50% BCL-2 expression was defined as double-expressor DLBCL. Results The mean age of the patients was 52.1±16.9 years. The mean Ki67 index was 73.0±17.0%. A total of 48.6% cases were of germinal center B-cell-like (GCB) subtype, and 59.6% cases were nodal. Double-expressor phenotype was noted in 35.8% of DLBCL cases. A significant association of double-expressor phenotype was noted with age, gender, Ki67 index and subtype of DLBCL. Double-expressor DLBCL had a higher mean age than non-double-expressor DLBCL. Similarly, double-expressor DLBCL had a higher Ki67 index. Moreover, double-expressor phenotype was associated with non-GCB subtype DLBCL. Conclusion We found a high proportion of double-expressor phenotype DLBCL in our population. Moreover, double-expressor phenotype DLBCL was associated with female gender, higher age, higher Ki67 and non-GCB subtype. The association of double-expressor DLBCL with a high Ki67 index and non-GCB subtype confers a poor prognostic significance of this variant of DLBCL, requiring more aggressive therapy.

Keywords: bcl-2; c-myc; diffuse large b-cell lymphoma; double-expressor; germinal center subtype; non-germinal center subtype.