title: Serum interleukin-6 has no discriminatory role in paraproteinaemia nor a prognostic role in multiple myeloma.
abstract: We determined interleukin-6 (IL-6) levels in the serum of 212 well-defined patients with newly diagnosed paraproteinaemia and evaluated its discriminatory value and prognostic role in multiple myeloma (MM). Results were compared with serum neural cell adhesion molecule and beta-2-microglobulin, both established prognostic MM markers. Paraproteinaemia-related diagnoses were: MM (60), other haematological diseases (46), solid tumours (35), autoimmune diseases (17) and monoclonal gammopathy of unknown significance (MGUS) (54). The range of IL-6 levels in all diagnostic groups overlapped widely and did not serve as a discriminatory marker in newly diagnosed paraproteinaemia even when patients with infection or fever (42) were excluded. In MM high IL-6 levels (>/= 50 pg/ml) were not associated with a shorter survival (P = 0.24). We compared our results with 20 published studies on serum IL-6 in paraproteinaemia and/or MM. IL-6 data have to be related to the assay used (bio- or immunoassay) and to the status of MM (newly diagnosed, during therapy, progressive disease). We conclude that serum IL-6 is not specific for paraproteinaemia-related diseases and will not serve as a reliable discriminatory or prognostic marker in paraproteinaemia and MM.
authors.affiliation: Department of Haematology, Leiden University Medical Centre, The Netherlands.
authors.forename: C G
authors.initials: CG
authors.lastname: Schaar
authors.forename: U
authors.initials: U
authors.lastname: Kaiser
authors.forename: S
authors.initials: S
authors.lastname: Snijder
authors.forename: F
authors.initials: F
authors.lastname: Ong
authors.forename: J
authors.initials: J
authors.lastname: Hermans
authors.forename: P F
authors.initials: PF
authors.lastname: Franck
authors.forename: J C
authors.initials: JC
authors.lastname: Kluin-Nelemans
mesh_terms: D002097:C-Reactive Protein / Q000378:metabolism; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D009101:Multiple Myeloma / Q000175:diagnosis; D019006:Neural Cell Adhesion Molecules / Q000097:blood; D010265:Paraproteinemias / Q000175:diagnosis*; D011379:Prognosis; D016019:Survival Analysis; D001613:beta 2-Microglobulin / Q000097:blood
chemical_list: D015850:Interleukin-6; D019006:Neural Cell Adhesion Molecules; D001613:beta 2-Microglobulin; D002097:C-Reactive Protein