title: The utility of BRAF V600E mutation-specific antibody VE1 for the diagnosis of hairy cell leukemia.
abstract: OBJECTIVE
  BRAF V600E mutation is characteristic of hairy cell leukemia (HCL). A V600E mutation-specific antibody, VE1, has been recently developed. We studied the diagnostic utility of this antibody in HCL and compared it with other B-cell neoplasms.
  
  
  METHODS
  VE1 activity was assessed using immunohistochemistry in 90 mature B-cell neoplasms, including HCL (n = 17), HCL variant (n = 6), chronic lymphocytic leukemia (CLL) (n = 20), and 47 other B-cell lymphomas. Most (87/90) specimens were formalin-fixed, paraffin-embedded bone marrow (BM) biopsy specimens decalcified in either hydrochloric acid or formic acid.
  
  
  RESULTS
  VE1 was positive in 15 (88%) cases of HCL and two (10%) cases of CLL and was negative in all other tumors assessed. The VE1-positive HCL cases showed uniform staining in all tumor cells, but intensity was variable. The two VE1-negative HCL cases had BRAF V600 mutations proven by molecular analysis. The two CLL cases positive with VE1 showed an atypical staining pattern with expression in a minority of lymphoma cells. Immunohistochemistry using the VE1 antibody had a sensitivity of 88% and a specificity of 97% for HCL.
  
  
  CONCLUSIONS
  VE1 immunohistochemistry is a useful and convenient surrogate for detecting BRAF V600E mutation in BM biopsy specimens decalcified with hydrochloric or formic acid-based solutions.
authors.affiliation: From the Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA;
authors.forename: Guldeep
authors.initials: G
authors.lastname: Uppal
authors.affiliation: From the Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA;
authors.forename: Vandi
authors.initials: V
authors.lastname: Ly
authors.affiliation: From the Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA;
authors.forename: Zi-Xuan
authors.initials: ZX
authors.lastname: Wang
authors.affiliation: From the Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA;
authors.forename: Renu
authors.initials: R
authors.lastname: Bajaj
authors.affiliation: From the Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA;
authors.forename: Charalambos C
authors.initials: CC
authors.lastname: Solomides
authors.affiliation: Ventana Medical Systems, Tucson, AZ; and.
authors.forename: Peter M
authors.initials: PM
authors.lastname: Banks
authors.affiliation: The University of Texas MD Anderson Cancer Center, Houston.
authors.forename: L Jeffrey
authors.initials: LJ
authors.lastname: Medeiros
authors.affiliation: From the Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA;
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Peiper
authors.affiliation: From the Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA; jerald.gong@jefferson.edu.
authors.forename: Jerald Z
authors.initials: JZ
authors.lastname: Gong
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology; D001402:B-Lymphocytes / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000276:immunology* / Q000378:metabolism; D001706:Biopsy; D006801:Humans; D007150:Immunohistochemistry; D007943:Leukemia, Hairy Cell / Q000175:diagnosis* / Q000235:genetics; D009154:Mutation / Q000235:genetics; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics*
chemical_list: D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; D048493:Proto-Oncogene Proteins B-raf
keywords: BRAF; Hairy cell leukemia; Immunohistochemistry; VE1