title: An unusual case of indolent B-cell lymphoma with distinct chronic lymphocytic leukemia and marginal zone differentiation according to the site of involvement.
abstract: The immunological profile of lymphoproliferative disorders is usually conserved whatever the involved site, thus allowing a reliable diagnosis from peripheral blood analysis, especially in small lymphocytic lymphoma/chronic lymphocytic lymphoma (SLL/CLL). Here we present a case wherein the cytology and immunophenotype of blood specimen and bone marrow argue in favor of SLL/CLL with a typical Matutes score (5/5), whereas the cyto-histology and immunophenotype of spleen specimen led to the diagnosis of splenic marginal zone B-cell lymphoma (SMZL). Moreover genomic analysis showed that the splenic cells displayed a SMZL signature. Whereas these data suggested the presence of 2 B-cell clones, the study of the mutational status of IgVH gene in blood and spleen demonstrated the presence of a single clone, which likely developed simultaneously along two distinct ways of differentiation according to the anatomic site suggesting here the predominant role of a micro-environmental factor in cell differentiation. Although rare, this kind of event must be kept in mind as a cause of discrepancies between diagnoses from different sites.
authors.affiliation: Service d'Hématologie Biologique, Hôpital Edouard Herriot, Lyon, France.
authors.forename: Lucile
authors.initials: L
authors.lastname: Baseggio
authors.forename: Sophie
authors.initials: S
authors.lastname: Gazzo
authors.forename: Evelyne
authors.initials: E
authors.lastname: Callet-Bauchu
authors.forename: Alexandra
authors.initials: A
authors.lastname: Traverse-Glehen
authors.forename: Catherine
authors.initials: C
authors.lastname: Thieblemont
authors.forename: Paul-André
authors.initials: PA
authors.lastname: Bryon
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Magaud
authors.forename: Françoise
authors.initials: F
authors.lastname: Berger
authors.forename: Pascale
authors.initials: P
authors.lastname: Felman
mesh_terms: D000368:Aged; D005803:Genes, Immunoglobulin; D006801:Humans; D016130:Immunophenotyping; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000097:blood* / Q000235:genetics; D016393:Lymphoma, B-Cell / Q000175:diagnosis*; D008297:Male; D009154:Mutation; D013160:Splenic Neoplasms / Q000175:diagnosis