title: BCL6, MUM1, and CD10 expression in mantle cell lymphoma.
abstract: Mantle cell lymphoma (MCL) characteristically express CD20, CD5, and cyclin-D1, carries the translocation t(11;14) (q13;q32) and typically has no expression of germinal center cell markers. So-called aberrant phenotypes such as CD5 negative and cyclin-D1-negative MCL have been described. Also few cases with CD10 and/or BCL-6 protein expression have been reported. We analyzed 127 MCL looking for the frequency of aberrant immunophenotype, CD10, BCL-6, and MUM1 expression. All cases were CD20 and cyclin-D1 positive, 96% expressed CD5, and 98% showed the t(11;14). BCL-6 expression was observed in 12% of the cases and MUM1 in 35%. No one case showed CD10 positivity in 30% or more neoplastic cells. Only 3 cases showed 10% to 20% of tumoral cells positive for CD10. MUM1 expression was observed in 67% of the BCL-6 positive cases. Thirty-two percent of the cases showed a MUM1+/BCL-6-/CD10- phenotype and 56% had a triple-negative-pattern. Aberrant phenotype is infrequent but not rare, and does not rule out a diagnosis of MCL in an otherwise typical case.
authors.affiliation: Consultoria em Patologia, Botucatu, SP, Brazil.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Gualco
authors.forename: Lawrence M
authors.initials: LM
authors.lastname: Weiss
authors.forename: William J
authors.initials: WJ
authors.lastname: Harrington
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Bacchi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D018956:CD5 Antigens / Q000096:biosynthesis; D056741:Cyclin D / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D005260:Female; D015973:Gene Expression Regulation, Leukemic; D018858:Germinal Center / Q000473:pathology; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D020522:Lymphoma, Mantle-Cell / Q000175:diagnosis / Q000276:immunology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015260:Neprilysin / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D015514:Oncogene Proteins, Fusion / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D051560:Proto-Oncogene Proteins c-bcl-6; D012189:Retrospective Studies; D014178:Translocation, Genetic
chemical_list: C084103:BCL6 protein, human; D014408:Biomarkers, Tumor; D018956:CD5 Antigens; D056741:Cyclin D; D004268:DNA-Binding Proteins; C529133:IGH-CCND1 fusion protein, human; D015514:Oncogene Proteins, Fusion; D051560:Proto-Oncogene Proteins c-bcl-6; D015260:Neprilysin