title: Identification of intracellular immunoglobulin in extramedullary myeloma.
abstract: We describe a patient with multiple myeloma characterized by clinically evident extramedullary metastasis and marked anaplastic alterations of neoplastic cells. We describe the technique that detected the presence of intracytoplasmic immunoglobulin IgGk in mature plasma cells from paraffin-fixed tissue obtained from an iliac lesion and in anaplastic tumor cells infiltrating a lymph node from which a biopsy specimen was taken three years later. These data confirm that both tissues were composed of a cell with identical origin. In addition, the immunohistochemical technique is applicable for the identification of other antigens present in paraffin-embedded tissue.
mesh_terms: D000368:Aged; D002462:Cell Membrane / Q000276:immunology; D005260:Female; D006801:Humans; D007085:Ilium / Q000473:pathology; D007124:Immunoenzyme Techniques; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis*; D007147:Immunoglobulin Light Chains / Q000032:analysis*; D007145:Immunoglobulin kappa-Chains / Q000032:analysis*; D008198:Lymph Nodes / Q000473:pathology; D009101:Multiple Myeloma / Q000276:immunology* / Q000473:pathology; D010503:Periodic Acid-Schiff Reaction; D010950:Plasma Cells / Q000276:immunology*
chemical_list: D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007147:Immunoglobulin Light Chains; D007145:Immunoglobulin kappa-Chains