title: Residual monotypic plasma cells in patients with waldenstrom macroglobulinemia after therapy.
abstract: Waldenström macroglobulinemia (WM) is currently defined as lymphoplasmacytic lymphoma involving bone marrow (BM) associated with a serum IgM paraprotein. WM is typically composed of small lymphocytes, plasmacytoid lymphocytes, and plasma cells in variable proportions, which can change after therapy. In this study, we assessed 41 WM cases that required chemotherapy, 39 showing persistent disease in restaging BM specimens. In 10 cases, there was persistent monotypic plasmacytosis in BM in the absence of demonstrable monotypic B cells. The monotypic plasma cells represented 0.5% to 46% of the cellularity and persisted 1 to 50 months after the last course of chemotherapy. The plasma cells were best quantified by immunohistochemical analysis on paraffin sections. We conclude that WM can persist as a pure plasma cell population after therapy. This finding has implications for the immunophenotypic assessment of WM after therapy and may explain persistent IgM paraproteinemia in patients with WM with no evidence of a clonal B-lymphocyte population.
authors.affiliation: Dept of Hematopathology, The University of Texas M.D. Anderson Cancer Center, Houston, 77030, USA.
authors.forename: Fareed H
authors.initials: FH
authors.lastname: Barakat
authors.forename: L Jeffrey
authors.initials: LJ
authors.lastname: Medeiros
authors.forename: Eric X
authors.initials: EX
authors.lastname: Wei
authors.forename: Sergej
authors.initials: S
authors.lastname: Konoplev
authors.forename: Pei
authors.initials: P
authors.lastname: Lin
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Jorgensen
mesh_terms: D000368:Aged; D058846:Antibodies, Monoclonal, Murine-Derived / Q000627:therapeutic use; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000276:immunology / Q000378:metabolism; D001854:Bone Marrow Cells / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D002452:Cell Count; D002871:Chromosome Banding / Q000379:methods; D005260:Female; D006801:Humans; D007075:Immunoglobulin M / Q000276:immunology; D007150:Immunohistochemistry; D007155:Immunologic Factors / Q000627:therapeutic use; D016130:Immunophenotyping; D008214:Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual; D010950:Plasma Cells / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D000069283:Rituximab; D008258:Waldenstrom Macroglobulinemia / Q000188:drug therapy* / Q000276:immunology / Q000473:pathology*
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D014408:Biomarkers, Tumor; D007075:Immunoglobulin M; D007155:Immunologic Factors; D000069283:Rituximab