Anaplastic plasmacytoma with XXXX lacking evidence of @entity1581 .

@entity1143 @entity706 @entity1581 @entity5 @entity14546 @entity3053 @entity13221 @entity3483
A case of plasmacytoma of the @entity1143 is reported with massive @entity3483 , which, most unusually, lacked @entity1581 , thereby making it difficult to distinguish from @entity706 . The @entity5 and @entity1143 contained large mononuclear @entity706 -like cells with distinct nucleoli. Immunohistochemistry revealed neither @entity706 markers nor clonal cytoplasmic nor cell surface immunoglobulins. @entity5 cells were stained with vimentin and the plasma cell markers, VS38c, @entity13221 ( @entity13221 ), and @entity14546 antibodies. Bone marrow contained small amounts of @entity5 consisting of similar cells. Electron microscopy showed well developed rough endoplasmic reticulum and peripherally positioned nuclei with euchromatin. Flow cytometry of bone marrow revealed a minimal involvement of @entity3053 -positive cells. Chromosomal analysis of marrow cells revealed a complex abnormal karyotype. A polymerase chain reaction demonstrated clonal re-arrangement of the immunoglobulin heavy-chain gene. The overall results indicate a clonal expansion of @entity5 cells with primitive plasma cell differentiation with the highly unusual feature of absent monotypic immunoglobulin. The study illustrates the need for a comprehensive array of techniques to distinguish such rare non-synthesizing and non-secretory plasmacytomas from @entity706 .
