No abstract available.
Adult ; Aged ; Base Sequence ; Bone Marrow/metabolism/pathology ; Female ; Formaldehyde/chemistry ; Gene Frequency ; Humans ; Male ; Middle Aged ; Multiple Myeloma/diagnosis/genetics ; Mutation ; Myeloid Differentiation Factor 88/chemistry/*genetics/metabolism ; Paraffin Embedding ; Sequence Analysis, DNA/*methods ; Waldenstrom Macroglobulinemia/diagnosis/genetics

OBJECTIVETo study the clinicopathologic features and differential diagnosis of splenic B-cell marginal zone lymphoma (SMZL) involving bone marrow.

METHODSThe clinical and pathologic features of 22 patients with SMZL were retrospectively studied. Immunophenotypic analysis was carried out by flow cytometry and immunohistochemistry. Immunoglobulin heavy chain rearrangement study was performed using polymerase chain reaction-based method.

RESULTSVillous lymphocytes were found in peripheral blood smears of 11/18 of the patients. In bone marrow aspirates, lymphocytosis (> 20%) was demonstrated in 15 cases (15/18) and villous lymphocytes in 6 cases (6/18). Flow cytometry showed CD19(+) CD20(+) FMC7(+) CD22(+) CD10(-) CD2(-) CD3(-) CD7(-) in 18 cases. Bone marrow biopsies of all the 22 patients revealed various degrees and patterns of neoplastic infiltration, as follows: mild (4 cases, 18.2%), moderate (11 cases, 50.0%) or severe (7 cases, 31.8%); intrasinusoidal (16 cases, 72.7%), interstitial (14 cases, 63.6%), nodular (11 cases, 50.0%) or diffuse (1 case, 4.5%). Reactive germinal center formation (CD23(+) bcl-2(-)) was found in 2 cases (91.0%). Immunohistochemical study showed the following results: CD20(+) PAX5(+) CD3(-) CD5(-) CD10(-) cyclin D1(-) CD23(-) CD43(-) Annexin A1(-) CD11C(-) CD25(-) in all the 22 cases, CD38(+) in 2 cases (9.1%) and CD138(+) in 2 cases (9.1%).

CONCLUSIONSDifferent and overlapping patterns of bone marrow involvement are observed in SMZL. As the histologic and immunophenotypic features are not specific to SMZL, distinction from other types of mature B-cell lymphomas is necessary.

Adult ; Aged ; Aged, 80 and over ; Antigens, CD20 ; metabolism ; Bone Marrow ; pathology ; Diagnosis, Differential ; Female ; Gene Rearrangement, B-Lymphocyte, Heavy Chain ; Humans ; Leukemia, Lymphocytic, Chronic, B-Cell ; metabolism ; pathology ; Lymphoma, B-Cell, Marginal Zone ; genetics ; metabolism ; pathology ; Lymphoma, Follicular ; metabolism ; pathology ; Lymphoma, Mantle-Cell ; metabolism ; pathology ; Male ; Middle Aged ; Neoplasm Invasiveness ; Retrospective Studies ; Splenic Neoplasms ; genetics ; metabolism ; pathology ; Waldenstrom Macroglobulinemia ; metabolism ; pathology