Prognostic value of plasma interleukin-6 levels in patients with chronic lymphocytic leukemia

Cancer. 2002 Sep 1;95(5):1071-5. doi: 10.1002/cncr.10772.


Background: Interleukin 6 (IL-6) is a B-cell growth and differentiation factor, which may promote the growth of B-cell neoplasms. In chronic lymphocytic leukemia (CLL) patients, IL-6 plasma levels increased in a stage-dependent manner, suggesting that IL-6 may be a useful prognostic marker. The purpose of this study is to fully assess the prognostic value of IL-6 in CLL patients.

Methods: We measured the plasma levels of IL-6 in 100 CLL patients using an enzyme-linked immunoassay method.

Results: Increasing levels of IL-6 significantly correlated with patient age, severity of anemia, Rai stage, white cell count, and beta-2-microglobulin (beta-2M). Although CLL patients did not differ significantly from the normal controls in the median IL-6 plasma level (P = 0.38), patients with advanced diseases (defined by Rai stage III/IV or beta-2M > 3.5) had a significantly higher median IL-6 plasma level than the normal controls (P < 0.05). Furthermore, in patients with advanced diseases, Cox regression hazards model showed that a higher IL-6 level correlated with shorter survival (P = 0.0001). Using IL-6 level of 3 pg/mL as a cutoff, patients with low IL-6 levels had a significantly longer overall survival than those with high IL-6 levels (log rank test, P = 0.002). In patients with CD38-positive CLL, patients with high IL-6 levels (> 3 pg/mL) had significantly shorter survival (P = 0.03). To conclude, IL-6 is a particularly useful predictor for survival in CLL patients with advanced diseases.

Conclusions: Our findings suggest that patients with advanced-stage CLL as well as high IL-6 plasma levels may require aggressive therapeutic approaches and special consideration for experimental therapy.

Publication types

  • Evaluation Study

MeSH terms

  • ADP-ribosyl Cyclase
  • ADP-ribosyl Cyclase 1
  • Adult
  • Aged
  • Aged, 80 and over
  • Antigens, CD*
  • Antigens, Differentiation / analysis
  • Biomarkers, Tumor / analysis*
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Humans
  • Interleukin-6 / blood*
  • Leukemia, Lymphocytic, Chronic, B-Cell / pathology*
  • Male
  • Membrane Glycoproteins
  • Middle Aged
  • NAD+ Nucleosidase / analysis
  • Neoplasm Staging / methods*
  • Predictive Value of Tests
  • Prognosis
  • Survival Analysis


  • Antigens, CD
  • Antigens, Differentiation
  • Biomarkers, Tumor
  • Interleukin-6
  • Membrane Glycoproteins
  • ADP-ribosyl Cyclase
  • CD38 protein, human
  • NAD+ Nucleosidase
  • ADP-ribosyl Cyclase 1