Clinical significance of interleukin-6 (IL-6) in the spread of gastric cancer: role of IL-6 as a prognostic factor

Gastric Cancer. 2005;8(2):124-31. doi: 10.1007/s10120-005-0315-x.


Background: It is becoming clear that various cytokines are associated with the spread of cancer cells. The purpose of this study was to compare interleukin (IL)-6 levels in patients with gastric cancer to elucidate the role of IL-6 in predicting the spread of tumors.

Methods: In 60 patients, we assessed the correlation of serum IL-6 (pg/ml) with stage, histological findings, hepatic metastasis, and related factors (hepatocyte growth factor [HGF], IL-1beta, tumor necrosis factor [TNF]-alpha, and transforming growth factor [TGF]-beta1). We also investigated the diagnostic significance of the IL-6 level for advanced gastric cancer and lymph node metastasis, as well as the association between IL-6 elevation and outcome. Finally, we examined the expression of IL-6 in tumor tissue.

Results: Significant relationships were seen between serum IL-6 and stage, depth of tumor invasion (pT), lymphatic invasion (ly), venons invasion (v)*, lymph node metastasis (pN), hepatic metastasis (cH), and HGF (P < 0.01; *P < 0.05). With regard to the diagnostic significance of the IL-6 level for advanced gastric cancer and lymph node metastasis, when the cutoff value of IL-6 was set at 1.97 pg/ml, the sensitivity was 81.8% and 87.5%; specificity was 66.7% and 58.3%; and accuracy was 77.1% and 72.9%, respectively. The 1- and 3-year cumulative survival rates for patients with an IL-6 value of more than 1.97 pg/ml (69.0% and 43.4%, respectively) were significantly lower than those for patients with an IL-6 value of 1.97 pg/ml or less (94.4% and 87.2%, respectively; P < 0.05). Immunohistochemical staining was positive for IL-6 in the cytoplasm of cancer cells.

Conclusion: We suspect that IL-6 is involved in cancer invasion and lymph node and/or hepatic metastasis. Our results indicate that IL-6 could be used as a prognostic factor for survival.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers / blood*
  • Biomarkers, Tumor / blood*
  • Female
  • Gene Expression Profiling
  • Humans
  • Interleukin-6 / biosynthesis
  • Interleukin-6 / blood*
  • Liver Neoplasms / secondary*
  • Lymphatic Metastasis
  • Male
  • Middle Aged
  • Neoplasm Invasiveness
  • Neoplasm Metastasis
  • Prognosis
  • Stomach Neoplasms / immunology*
  • Stomach Neoplasms / pathology*


  • Biomarkers
  • Biomarkers, Tumor
  • Interleukin-6