title: Partial lack of BCL2 in follicular lymphoma: An unusual immunohistochemical staining pattern explained by ongoing BCL2 mutation.
abstract: Follicular lymphomas are characterized by overexpression of BCL2 which, in the large majority of cases, is due to a t(14;18) translocation which juxtaposes the BCL2 locus to the immunoglobulin heavy chain locus (IGH). Here, we report partial absence of BCL2 immunohistochemical staining in a case of FL, due to a mutation in the part of BCL2 that encodes the epitope for the most frequently used antibody against BCL2. This finding shows that mutations in BCL2 occur in an ongoing process in follicular which can give rise to unusual immunohistochemical staining patterns.
authors.affiliation: Department of Pathology, Radboud University Medical Center, Nijmegen, The Netherlands. Electronic address: Michiel.vandenBrand@radboudumc.nl.
authors.forename: Michiel
authors.initials: M
authors.lastname: van den Brand
authors.affiliation: Department of Pathology, Hospital del Mar-IMIM, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Mar
authors.initials: M
authors.lastname: Garcia-Garcia
authors.affiliation: Department of Pathology, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Janneke J M
authors.initials: JJ
authors.lastname: Mathijssen
authors.affiliation: Department of Pathology, Hospital del Mar-IMIM, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Lluis
authors.initials: L
authors.lastname: Colomo
authors.affiliation: Department of Pathology, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Patricia J T A
authors.initials: PJ
authors.lastname: Groenen
authors.affiliation: Department of Pathology, Hospital del Mar-IMIM, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Serrano
authors.affiliation: Department of Pathology, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: J Han J M
authors.initials: JH
authors.lastname: van Krieken
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis* / Q000235:genetics*; D004252:DNA Mutational Analysis; D015536:Down-Regulation; D006801:Humans; D007150:Immunohistochemistry; D008224:Lymphoma, Follicular / Q000737:chemistry* / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011237:Predictive Value of Tests; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis* / Q000235:genetics*; D015203:Reproducibility of Results
chemical_list: C000595707:BCL2 protein, human; D014408:Biomarkers, Tumor; D019253:Proto-Oncogene Proteins c-bcl-2
keywords: BCL2; Follicular lymphoma; Immunohistochemistry