title: The utility of CD20 and CD43 in subclassification of low-grade B-cell lymphoma on paraffin sections.
abstract: To identify phenotypic differences among the low-grade lympho-proliferative disorders in paraffin-embedded tissue, we studied 49 cases. All 22 follicular small cleaved cell lymphomas (FSC) were CD43 negative and CD20 positive. In contrast, of 20 small lymphocytic lymphomas (SL), 90% were CD20 positive, 85% were CD43 positive, and 75% were positive for both. Of three lymphomas of intermediate differentiation (IDL), two were CD20 positive and two were CD43 positive. All four monocytoid B-cell lymphomas were positive for CD20 and 50% (two cases) were positive for CD43. Some 86% of 14 chronic lymphocytic leukemias (CLL) (on cytospins) were positive for CD43; all nine of the CLL studied for CD20 were positive and 89% (8/9) expressed both antibodies CD5 expression (on frozen sections or cytospin preparations) was compared to CD43 in 21 cases of SL and CLL. Some 77% were positive for both CD5 and CD20. All seven of the CD5-positive SL also expressed CD43. The antibody MT2 was also examined with the following results: FSC, 16/20 (80%) positive; SL, 18/19 (94%) positive; MBC, 3/3 positive; and ILL, 2/3 positive. All 56 cases tested were CD45RO (UCHL1) negative. We conclude that CD43 is expressed on most cases of low-grade lymphoproliferative disorders with the exception of FSC. Its pattern of expression seems similar to CD5; however, unlike CD5, CD43 can be studied in formalin-fixed tissue. MT2 is not helpful in distinguishing among these lesions.
authors.affiliation: Department of Pathology, Medical College of Virginia, Richmond, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Contos
authors.forename: M J
authors.initials: MJ
authors.lastname: Kornstein
authors.forename: D J
authors.initials: DJ
authors.lastname: Innes
authors.forename: J
authors.initials: J
authors.lastname: Ben-Ezra
mesh_terms: D015703:Antigens, CD / Q000032:analysis*; D018951:Antigens, CD20; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis*; D018956:CD5 Antigens; D002908:Chronic Disease; D006801:Humans; D007150:Immunohistochemistry; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000276:immunology / Q000473:pathology; D007945:Leukemia, Lymphoid / Q000276:immunology / Q000473:pathology; D051917:Leukosialin; D016393:Lymphoma, B-Cell / Q000276:immunology* / Q000473:pathology*; D008224:Lymphoma, Follicular / Q000276:immunology / Q000473:pathology; D016612:Paraffin Embedding; D012795:Sialoglycoproteins / Q000032:analysis*
chemical_list: D015703:Antigens, CD; D018951:Antigens, CD20; D000944:Antigens, Differentiation, B-Lymphocyte; D018956:CD5 Antigens; D051917:Leukosialin; C465014:SPN protein, human; D012795:Sialoglycoproteins