title: B-cell cutaneous lymphoid hyperplasia representing progressive transformation of germinal center: a report of 2 cases.
abstract: Cutaneous lymphoid hyperplasia (CLH) is a reactive polyclonal benign lymphoproliferative process predominantly composed of B cells or T cells, either localized or disseminated. The authors report histomorphologic, immunophenotypic, and genotypic findings of 2 cases of B-cell CLH demonstrating progressive transformation of germinal center (PTGC). Histologically, most of the lymphoid follicles were PTGCs with a few hyperplastic germinal centers. PTGC was characterized by enlarged but well-circumscribed follicles without clear demarcation of the germinal center and mantle zone, which contained a predominance of small lymphocytes and variable numbers of centrocytes, centroblasts, and immunoblasts. However, there were no centroblasts and immunoblasts resembling lymphocytic and/or histiocytic Reed-Sternberg cell variants in nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) in either lesion. These unusual CLHs should be differentiated from the primary cutaneous marginal zone B-cell lymphoma, primary cutaneous follicular lymphoma, particularly "floral variant," or NLPHL. To avoid overdiagnosis and overtreatment, immunophenotypic and genotypic studies are required along with careful morphologic examination.
authors.affiliation: Department of Pathology and Clinical Laboratories, Gunma Cancer Center Hospital, Ohta, Japan. mkojima@gunma-cc.jp
authors.forename: Masaru
authors.initials: M
authors.lastname: Kojima
authors.forename: Shinji
authors.initials: S
authors.lastname: Sakurai
authors.forename: Ken
authors.initials: K
authors.lastname: Shimizu
authors.forename: Hideaki
authors.initials: H
authors.lastname: Itoh
mesh_terms: D000368:Aged; D001402:B-Lymphocytes / Q000276:immunology / Q000473:pathology*; D015415:Biomarkers / Q000378:metabolism; D002471:Cell Transformation, Neoplastic / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D019085:Fluorescent Antibody Technique, Direct; D018858:Germinal Center / Q000473:pathology*; D006801:Humans; D016130:Immunophenotyping; D018442:Lymphoma, B-Cell, Marginal Zone / Q000175:diagnosis; D008224:Lymphoma, Follicular / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D019310:Pseudolymphoma / Q000276:immunology / Q000473:pathology*; D012871:Skin Diseases / Q000276:immunology / Q000473:pathology*; D012878:Skin Neoplasms / Q000175:diagnosis
chemical_list: D015415:Biomarkers