title: Immunophenotypic and cytogenetic comparison of Waldenstrom's macroglobulinemia with splenic marginal zone lymphoma.
abstract: Some B-cell lymphoproliferative disorders displaying a serum monoclonal immunoglobulin (Ig) M protein could be difficult to differentiate from Waldenstrom's macroglobulinemia (WM). We report on the immunophenotypic and cytogenetic characteristics of 85 patients with WM and compare them with 29 patients with splenic marginal zone lymphoma (SMZL). For immunophenotyping, WM and SMZL constantly expressed panB-cell markers (CD19, CD20, CD22, and surface Ig). However, there were differences in the k/l ratio (1.2:1 for SMZL and 4.5:1 for WM) and in some markers such as CD22 and CD11c, which were overexpressed in patients with SMZL compared with patients with WM, whereas CD25 was more frequently positive in WM (88% vs. 44%). The CD103 antigen was always negative in WM, whereas it was positive in 40% of SMZL cases. The monoclonal antibody FMC7 was usually positive in both entities: heterogeneous in WM but homogeneous in SMZL. The combination of CD25 and CD22 could differentiate between WM and SMZL. The principal molecular abnormality in WM is 6q deletion (30% in our experience), whereas in SMZL the most common abnormalities are loss of 7q (19%) along with +3q (19%) and +5q (10%). Interestingly, the incidence of IgH rearrangement was low in WM (12%) and SMZL (10%). Immunophenotypic and molecular cytogenetic studies could help to distinguish WM from SMZL.
authors.affiliation: Hematology Service, Hospital Universitario de Salamanca, Paseo san Vicente 58-182, 37007 Salamanca, Spain.
authors.forename: Enrique M
authors.initials: EM
authors.lastname: Ocio
authors.forename: Jesus M
authors.initials: JM
authors.lastname: Hernandez
authors.forename: Gema
authors.initials: G
authors.lastname: Mateo
authors.forename: Maria L
authors.initials: ML
authors.lastname: Sanchez
authors.forename: Belen
authors.initials: B
authors.lastname: Gonzalez
authors.forename: Belen
authors.initials: B
authors.lastname: Vidriales
authors.forename: Norma C
authors.initials: NC
authors.lastname: Gutierrez
authors.forename: Alberto
authors.initials: A
authors.lastname: Orfao
authors.forename: Jesus F
authors.initials: JF
authors.lastname: San Miguel
mesh_terms: D015703:Antigens, CD; D002869:Chromosome Aberrations; D003582:Cytogenetics; D006801:Humans; D016130:Immunophenotyping; D017404:In Situ Hybridization, Fluorescence; D008223:Lymphoma / Q000235:genetics* / Q000276:immunology*; D009693:Nucleic Acid Hybridization; D011947:Receptors, Antigen, B-Cell / Q000032:analysis; D013160:Splenic Neoplasms; D008258:Waldenstrom Macroglobulinemia / Q000235:genetics* / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D011947:Receptors, Antigen, B-Cell