title: Immunohistological analysis in diagnosis of plasma cell myeloma based on cytoplasmic kappa/lambda ratio of CD38-positive plasma cells.
abstract: The accurate determination of cytoplasmic immunoglobulin (cIg) light chain (LC) expression is important to differentiate reactive plasmacytosis from a clonal plasma cell neoplasm such as plasma cell myeloma (PCM). Through retrospective analysis, we studied the cytoplasmic kappa/lambda  ratio of CD38-positive plasma cells in the bone marrow from 19 PCM patients and 19 controls. To demonstrate cIg LC expression, the bone marrow was immunostained for IgA, IgG, IgM, kappa, and lambda. The kappa/lambda ratio was defined as the ratio of the kappa-positive cell to the lambda-positive  cell in plasma cells. PCM cells were distinguished from normal plasma cells by cut-off levels between 0.59 and 4.0, a sensitivity of 94.7%, and a specificity of 94.7%. The detection of the cytoplasmic kappa/lambda ratio of CD38-positive plasma cells may be a useful tool in the diagnosis of  PCM and the correct diagnosis of PCM may be achieved more simply.
authors.affiliation: Department of Internal Medicine,Osaka Medical College, Osaka, Japan. in1304@poh.osaka-med.ac.jp
authors.forename: Shoko
authors.initials: S
authors.lastname: Nakayama
authors.forename: Taiji
authors.initials: T
authors.lastname: Yokote
authors.forename: Yuji
authors.initials: Y
authors.lastname: Hirata
authors.forename: Kazuki
authors.initials: K
authors.lastname: Iwaki
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Akioka
authors.forename: Takuji
authors.initials: T
authors.lastname: Miyoshi
authors.forename: Uta
authors.initials: U
authors.lastname: Nishiwaki
authors.forename: Yuki
authors.initials: Y
authors.lastname: Masuda
authors.forename: Nobuya
authors.initials: N
authors.lastname: Hiraoka
authors.forename: Ayami
authors.initials: A
authors.lastname: Takayama
authors.forename: Yasuichiro
authors.initials: Y
authors.lastname: Nishimura
authors.forename: Motomu
authors.initials: M
authors.lastname: Tsuji
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Hanafusa
mesh_terms: D051997:ADP-ribosyl Cyclase 1 / Q000378:metabolism*; D000368:Aged; D000369:Aged, 80 and over; D001854:Bone Marrow Cells / Q000378:metabolism / Q000473:pathology; D016022:Case-Control Studies; D003593:Cytoplasm / Q000378:metabolism; D005260:Female; D006801:Humans; D007145:Immunoglobulin kappa-Chains / Q000378:metabolism*; D007146:Immunoglobulin lambda-Chains / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000175:diagnosis*; D010950:Plasma Cells / Q000378:metabolism* / Q000473:pathology
chemical_list: D007145:Immunoglobulin kappa-Chains; D007146:Immunoglobulin lambda-Chains; D051997:ADP-ribosyl Cyclase 1