title: Prognostic value of serum interleukin-6 in diffuse large-cell lymphoma.
abstract: BACKGROUND
  Interleukin-6 has important lymphoid bioregulatory effects, and serum levels of interleukin-6 are often elevated in patients with lymphoma.
  
  
  OBJECTIVE
  To determine the relation between serum levels of interleukin-6 before treatment and outcome in patients with diffuse large-cell lymphoma.
  
  
  METHODS
  Retrospective cohort analysis with multivariate analysis.
  
  
  METHODS
  Tertiary referral center.
  
  
  METHODS
  118 untreated patients with diffuse large-cell lymphoma who were enrolled in frontline chemotherapy protocols and 45 healthy controls.
  
  
  METHODS
  Serum levels of interleukin-6 were measured by using a sensitive enzyme-linked immunosorbent assay. Levels below the upper limit of the range for controls were considered normal. Outcomes were complete response, failure-free survival, and overall survival.
  
  
  RESULTS
  Serum levels of interleukin-6 were higher in patients with lymphoma (median, 4.6 pg/ml [range, undetectable to 224 pg/mL]) than in controls (median, undetectable [range, undetectable to 4.3 pg/mL]) (P = 0.009). The complete response rate was 95% for persons with normal interleukin-6 levels and 55% for persons with high interleukin-6 levels (P = 0.001). Patients with high interleukin-6 levels had inferior failure-free and overall survival rates (P < 0.001 for both comparisons). The actuarial 4-year failure-free and overall survival rates were 72% and 85%, respectively, for persons with normal interleukin-6 levels and 37% and 46%, respectively, for persons with high interleukin-6 levels. In multivariate analysis, interleukin-6 was selected as the most significant predictor of complete response and failure-free survival. Failure-free and overall survival of patients stratified according to International Prognostic Index score could be further stratified by interleukin-6 level (P < or = 0.03 for all comparisons).
  
  
  CONCLUSIONS
  In patients with diffuse large-cell lymphoma, serum interleukin-6 levels are an independent prognostic factor for complete response and failure-free survival.
authors.affiliation: University of Texas M.D. Anderson Cancer Center, Houston, USA.
authors.forename: H A
authors.initials: HA
authors.lastname: Preti
authors.forename: F
authors.initials: F
authors.lastname: Cabanillas
authors.forename: M
authors.initials: M
authors.lastname: Talpaz
authors.forename: S L
authors.initials: SL
authors.lastname: Tucker
authors.forename: J F
authors.initials: JF
authors.lastname: Seymour
authors.forename: R
authors.initials: R
authors.lastname: Kurzrock
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D018572:Disease-Free Survival; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D016403:Lymphoma, Large B-Cell, Diffuse / Q000097:blood* / Q000188:drug therapy / Q000401:mortality; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D015850:Interleukin-6