Higher levels of interleukin-6 in cystic fluids from patients with malignant versus benign ovarian tumors correlate with decreased hemoglobin levels and increased platelet counts

Cancer. 1995 Feb 15;75(4):1004-9. doi: 10.1002/1097-0142(19950215)75:4<1004::aid-cncr2820750416>3.0.co;2-g.


Background: Recently, high pretreatment platelet counts and low pretreatment hemoglobin levels were found to be negative prognostic factors in patients with ovarian cancer. Interleukin-6 (IL-6) is a multifunctional cytokine with a diversity of functions leading to the induction of C-reactive protein (CRP), increased platelet counts, and low hemoglobin levels. Different epithelial ovarian cancer cell lines are found to produce varying amounts of IL-6. In this study, a possible relationship between IL-6 levels in cystic fluids of benign and malignant ovarian tumors and pretreatment serum CRP, platelet counts, and hemoglobin levels was evaluated.

Methods: A bioassay and enzyme-linked immunosorbent assay (ELISA) were performed to determine the IL-6 levels in cystic fluids and serum from 42 patients with benign and malignant ovarian tumors.

Results: The median IL-6 level was higher in cystic fluids of malignant tumors (n = 21) when compared with cystic fluids of benign tumors (n = 21) (P < 0.01 for bioassay and ELISA). Serum IL-6 levels in patients with malignant tumors were not significantly higher compared with IL-6 levels in patients with benign tumors, whereas CRP levels were higher in patients with malignant tumors (P < 0.01). Cystic fluid IL-6 levels were related to serum CRP levels (r = 0.60, P < 0.01 [bioassay]; r = 0.41, P < 0.01 [ELISA]), and were related inversely to hemoglobin levels (r = -0.57, P < 0.01 [bioassay]; r = 0.54, P < 0.01 [ELISA]).

Conclusions: IL-6 levels are higher in cystic fluids of malignant ovarian tumors compared with benign tumors. The relationship of cystic fluid IL-6 levels with CRP, platelet counts, and hemoglobin levels suggests a possible causative role of tumor-derived IL-6 in the appearance of general side effects of ovarian cancer, which recently have been recognized as prognostic factors.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / blood
  • Adenocarcinoma / immunology*
  • Adenocarcinoma / pathology
  • Cystadenoma / blood
  • Cystadenoma / immunology*
  • Cystadenoma / pathology
  • Female
  • Hemoglobins / analysis
  • Humans
  • Interleukin-6 / analysis*
  • Interleukin-6 / blood
  • Neoplasm Staging
  • Ovarian Neoplasms / blood
  • Ovarian Neoplasms / immunology*
  • Ovarian Neoplasms / pathology
  • Platelet Count


  • Hemoglobins
  • Interleukin-6