Aberrant Expression of Lymphoid Enhancer-Binding Factor 1 (LEF1) in Hodgkin Lymphoma

Diagnostic utility of lymphocyte enhancer factor 1 in aggressive B-cell lymphoma with MYC rearrangement

OBJECTIVES

We sought to investigate the diagnostic value of lymphocyte enhancer factor 1 (LEF1) expression in aggressive B-cell lymphomas (BCL) with MYC gene rearrangement (MYC-R).

METHODS

Sixty-seven cases of BCL were studied and included Burkitt lymphoma (BL) (23 cases); diffuse large B-cell lymphoma (DLBCL), not otherwise specified (NOS) with MYC-R (13 cases); and DLBCL/high-grade B-cell lymphoma with MYC, BCL2, and/or BCL6 rearrangements (double-hit [DH] or triple-hit [TH], 17 cases). Random DLBCL-NOS (14 cases) without MYC-R was recruited as a control group. By immunohistochemical stains, 3 patterns of LEF1 staining were recorded as pattern 0 (negative), pattern 1 (weak and heterogeneous staining, <80%), and pattern 2 (moderate/strong and uniform staining, ≥80%).

RESULTS

Pattern 1 can be seen in all BCLs with MYC-R included in this study and more commonly seen in DLBCL without MYC-R (8/14 cases). Pattern 2 is characteristic (positive predictive value = 86%) for Epstein-Barr virus (EBV)-negative BL, while pattern 0 was seen in 22 (76%) of 29 cases of DLBCL-MYC-R/DH/TH (P < .001). Seven of 8 EBV-positive BL cases showed pattern 0, which was completely opposite to the common pattern 2 in EBV-negative BL (12/15 cases). Pattern 2 was not detected in all DH/TH cases.

CONCLUSIONS

Weak and heterogeneous staining of LEF1 can be seen in all the BCLs with and without MYC-R. Strong and uniform staining of LEF1 is highly characteristic of EBV-negative BL among all aggressive BCLs with MYC-R, while the negative staining of LEF1 is mostly suggestive of DLBCL-MYC-R/DH/TH. Lymphocyte enhancer factor 1 provides additional diagnostic value in the differentiation of BL from other aggressive BCLs with MYC-R, especially in a limited specimen.

Updates in Immunohistochemistry for Hematopoietic and Lymphoid Neoplasms

CONTEXT.—

In their 2014 article "New Immunohistochemistry for B-cell Lymphoma and Hodgkin Lymphoma," Zhang and Aguilera reviewed new immunohistochemical markers for B-cell lymphoma and Hodgkin lymphoma and described how to use these markers for correct lymphoma diagnoses, using the 2008 World Health Organization classifications. Recently, the World Health Organization's WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues published 2022 updates, and, in quick sequence, a second group published an alternative International Consensus Classification of myeloid neoplasms, acute leukemias, and mature lymphoid neoplasms. Regardless of the system a hematopathologist chooses to follow, updates in the immunohistochemical diagnosis of disease are described in both publications as well as in the primary literature. In addition to updated classifications, the increasing use of small biopsy samples for the evaluation of lymphadenopathy continues to challenge hematopathology diagnosis and increase the utilization of immunohistochemistry.

OBJECTIVE.—

To review new immunohistochemical markers or new uses of previously known immunohistochemical markers in the evaluation of hematolymphoid neoplasia for the practicing hematopathologist.

DATA SOURCES.—

Data were obtained from a literature review and personal practice experience.

CONCLUSIONS.—

The practicing hematopathologist requires knowledge of the ever-expanding repertoire of immunohistochemistry for the diagnosis and treatment of hematolymphoid neoplasia. New markers presented in this article help to complete our understanding of disease, diagnosis, and management.

Diagnosing Lymphoma on Core Needle Biopsy and the Challenging Role of Immunohistochemistry

Publications and primary literature both describe the latest advancements in immunohistochemical diagnosis of lymphomas. Along with the updated categorizations, the growing reliance on small biopsy samples to assess lymphoma poses a constant difficulty in hematopathology diagnosis and heightens the demand for immunohistochemistry (IHC). This study aimed to provide practicing lymphoma and hematopathologists with an overview of novel immunohistochemical markers and new applications of already established immunohistochemistry markers to be helpful in lymphoma diagnosis, especially in core needle biopsies. The information was sourced from a review of relevant literature and personal experience gained through professional practice. To effectively diagnose and treat hematolymphoid neoplasms, we need to have a comprehensive understanding of the constantly evolving range of immunohistochemistry studies. This article introduced new markers that contribute to our overall knowledge of the disease, diagnosis, and treatment. The addition of these markers might be helpful in supporting the tumor diagnosis on limited sample material obtained from needle biopsies.