title: [Detection of serum free light chain and its clinical significance in nonsecretory multiple myeloma].
abstract: OBJECTIVE
  To explore the clinical significance of serum free light chain (sFLC) levels in nonsecretory multiple myeloma (NSMM).
  
  
  METHODS
  Nine NSMM patients were hospitalized in our department from Feb 2002 to Sep 2006 and no M-components was found in their serum and urine by immunofixation electrophoresis (IFE). sFLC was assayed by immuno-nephelometry. The clonality of sFLC was estimated by serum kappa:lambda sFLC ratio. Meanwhile, serum immunoglobulin, total kappa and lambda light chain level were also determined in these patients.
  
  
  RESULTS
  Increased serum concentrations of either kappa or lambda sFLC (and abnormal kappa/lambda ratios) were detected in 6 of 9 patients with NSMM although their serum immunoglobulin levels were not elevated and total kappa:lambda light chain ratios (1.32 - 2.20) were in the reference range. All the 9 patients had clonal IgH gene rearrangements.
  
  
  CONCLUSIONS
  Quantification of sFLC by immuno-nephelometry is more sensitive than that of serum total light chain measurement and is helpful in estimating the clonality of the light chain in patients with NSMM.
authors.affiliation: Department of Hematology, Changzheng Hospital, Shanghai 200003, China.
authors.forename: Hai-Fei
authors.initials: HF
authors.lastname: Chen
authors.forename: Jian
authors.initials: J
authors.lastname: Hou
authors.forename: Zhen-Gang
authors.initials: ZG
authors.lastname: Yuan
authors.forename: Dong-Xing
authors.initials: DX
authors.lastname: Wang
authors.forename: Wei-Jun
authors.initials: WJ
authors.lastname: Fu
authors.forename: Yu-Bao
authors.initials: YB
authors.lastname: Chen
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007147:Immunoglobulin Light Chains / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000097:blood*; D009391:Nephelometry and Turbidimetry; D012680:Sensitivity and Specificity
chemical_list: D007147:Immunoglobulin Light Chains