title: Diagnostic Utility of Lymphoid Enhancer Binding Factor 1 Immunohistochemistry in Small B-Cell Lymphomas.
abstract: OBJECTIVE
  Recent studies have shown that lymphoid enhancer binding factor 1 (LEF1) is a useful marker for chronic lymphocytic B-cell leukemia (CLL)/small lymphocytic lymphoma. Yet, it is not still being widely used in a diagnostic setting. In this study, we document the experience with LEF1 immunohistochemistry during routine diagnostics.
  
  
  METHODS
  In total, 191 B-cell lymphoma cases from Hammersmith Hospital, Imperial College NHS Healthcare Trust (London, UK) were investigated by immunohistochemistry for LEF1 during routine diagnostic workup. These cases included both bone marrow trephines and lymph node biopsy specimens. The monoclonal antibody clone EPR2029Y was used.
  
  
  RESULTS
  LEF1 expression was strong and diffuse (>70% of cells) in most cases. Few CLL cases showed a staining in proliferation centers only. Seventy-seven of 80 CLL cases expressed LEF1. Other entities expressing LEF1 included one of 38 follicular lymphomas, two of 33 marginal zone lymphomas, and one diffuse large B-cell lymphoma with a background of follicular lymphoma grade 3B. Sensitivity for LEF1 for the diagnosis of CLL was 0.96, and specificity was 0.93.
  
  
  CONCLUSIONS
  In this study, we could demonstrate the diagnostic utility of LEF1. LEF1 is a sensitive and specific marker for CLL and is helpful in the diagnosis of diagnostically challenging small B-cell lymphomas.
authors.affiliation: From the Department of Cellular and Molecular Pathology, Hammersmith Hospital Campus, Imperial College Healthcare NHS Trust, London, UK; and.|Institute of Pathology, University Hospital Basel, Basel, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Menter
authors.affiliation: From the Department of Cellular and Molecular Pathology, Hammersmith Hospital Campus, Imperial College Healthcare NHS Trust, London, UK; and.
authors.forename: Pritesh
authors.initials: P
authors.lastname: Trivedi
authors.affiliation: From the Department of Cellular and Molecular Pathology, Hammersmith Hospital Campus, Imperial College Healthcare NHS Trust, London, UK; and.
authors.forename: Raida
authors.initials: R
authors.lastname: Ahmad
authors.affiliation: From the Department of Cellular and Molecular Pathology, Hammersmith Hospital Campus, Imperial College Healthcare NHS Trust, London, UK; and.
authors.forename: Rashpal
authors.initials: R
authors.lastname: Flora
authors.affiliation: Institute of Pathology, University Hospital Basel, Basel, Switzerland.
authors.forename: Stephan
authors.initials: S
authors.lastname: Dirnhofer
authors.affiliation: Institute of Pathology, University Hospital Basel, Basel, Switzerland.
authors.forename: Alexandar
authors.initials: A
authors.lastname: Tzankov
authors.affiliation: From the Department of Cellular and Molecular Pathology, Hammersmith Hospital Campus, Imperial College Healthcare NHS Trust, London, UK; and.
authors.forename: Kikkeri N
authors.initials: KN
authors.lastname: Naresh
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D006801:Humans; D007150:Immunohistochemistry; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000175:diagnosis*; D051821:Lymphoid Enhancer-Binding Factor 1 / Q000032:analysis / Q000096:biosynthesis*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; C497573:LEF1 protein, human; D051821:Lymphoid Enhancer-Binding Factor 1
keywords: CLL; Immunohistochemistry; LEF1; Routine diagnostics