title: Primary cutaneous B-cell lymphoma (marginal zone) with prominent T-cell component and aberrant dual (T and B) genotype; diagnostic usefulness of laser-capture microdissection.
abstract: The presence of a dominant B- or T-cell clone is an important diagnostic criterion for distinguishing cutaneous lymphomas from lymphoid reactive infiltrates. Rarely, a combined B- and T-cell rearrangement can be detected from a single sample. In such instances, genotypic analysis does not permit differentiation of the coexistence of a T- and B-cell lymphoma from a single clone harbouring a monoclonal rearrangement for both immunoglobulin heavy chain and T-cell receptor genes. We herein report a case of a skin tumour consistent with a dense cutaneous lymphoid infiltrate showing a double prominent B- and T-cell component. A dual B- and T-cell clonality was detected by polymerase chain reaction from whole-tissue DNA sample. Genotypic analysis with DNA, obtained after laser-assisted microdissection from the B-cell population, again showed both T- and B-cell monoclonal rearrangements. Conversely, the microdissected T-cell population did not reveal a clonal pattern. The diagnosis of cutaneous B-cell lymphoma with a dual B- and T-cell genotype was established. This description illustrates the diagnostic usefulness of laser-capture microdissection in cutaneous lymphomas presenting dual genotype.
authors.affiliation: Department of Dermatology Laboratory of Cytogenetics and Molecular Biology, Hospital del Mar-Imas, Passeig Marítim 25-29, 08003- Barcelona, Spain. fgallardo@imas.imim.es
authors.forename: F
authors.initials: F
authors.lastname: Gallardo
authors.forename: R M
authors.initials: RM
authors.lastname: Pujol
authors.forename: B
authors.initials: B
authors.lastname: Bellosillo
authors.forename: D
authors.initials: D
authors.lastname: Ferrer
authors.forename: M
authors.initials: M
authors.lastname: García
authors.forename: C
authors.initials: C
authors.lastname: Barranco
authors.forename: M
authors.initials: M
authors.lastname: Planagumà
authors.forename: S
authors.initials: S
authors.lastname: Serrano
mesh_terms: D000368:Aged; D004273:DNA, Neoplasm / Q000235:genetics; D005260:Female; D015322:Gene Rearrangement, B-Lymphocyte; D015329:Gene Rearrangement, T-Lymphocyte; D005838:Genotype; D006801:Humans; D016393:Lymphoma, B-Cell / Q000235:genetics / Q000473:pathology*; D042282:Microdissection / Q000379:methods*; D014411:Neoplastic Stem Cells / Q000473:pathology*; D016133:Polymerase Chain Reaction / Q000379:methods; D012878:Skin Neoplasms / Q000235:genetics / Q000473:pathology*; D013601:T-Lymphocytes
chemical_list: D004273:DNA, Neoplasm