title: Trends of IL-6 and IL-8 levels in patients with recurrent breast cancer: preliminary report.
abstract: BACKGROUND
  We reported that IL-6 and IL-8 levels at the beginning of treatment are predictive indicators of response to therapy and prognosis of patients with recurrent breast cancer. The aim of this study was to investigate the trend of IL-6 and IL-8 levels in heavily pretreated patients with recurrent breast cancer.
  
  
  METHODS
  Cytokine level trends in 12 patients heavily pretreated with anthracyclines were studied. Patients were divided into two groups according to the objective response. There were 5 partial response (PR)/no change (NC), and 7 progressive disease (PD) patients. Blood was taken every four weeks. IL-6 was measured by chemiluminescent enzyme immunoassay. IL-8 was measured by ELISA.
  
  
  RESULTS
  The pretreatment level of IL-6 in the PR/NC group (11.0+/-2.1 pg/ml) was significantly lower than that (15.3+/-2.7 pg/ml) in the PD group. However, there was no difference in IL-8 level between the PR/NC group (12.5+/-5.5 pg/ml) and the PD group (11.5+/-1.1 pg/ml). IL-6 levels in the PR/NC group were maintained within normal levels or decreased to within normal levels after treatment, while levels of IL-6 in the PD group gradually increased until the time of patient death. A decrease in IL-8 level after treatment was observed in only one patient in the PR/NC group. Mild increase of IL-8 levels was observed in the PD group.
  
  
  CONCLUSIONS
  Continuous elevation of IL-6 levels indicates poor prognosis in heavily pretreated patients with recurrent breast cancer. Combination therapy including agents that reduce IL-6 levels will be a new strategy for aggressively treating recurrent breast cancer.
authors.affiliation: Emergency and Critical Care Medicine, Gunma University School of Medicine, 3-39-15 Showa-machi, Maebashi, Gunma 371-8511, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yokoe
authors.forename: Y
authors.initials: Y
authors.lastname: Iino
authors.forename: Y
authors.initials: Y
authors.lastname: Morishita
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000097:blood* / Q000188:drug therapy / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007124:Immunoenzyme Techniques; D015850:Interleukin-6 / Q000097:blood*; D016209:Interleukin-8 / Q000097:blood*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000097:blood* / Q000188:drug therapy / Q000276:immunology*; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D016896:Treatment Outcome; D000093242:Interleukin-6 Inhibitors
chemical_list: D000903:Antibiotics, Antineoplastic; D015850:Interleukin-6; D016209:Interleukin-8; D000093242:Interleukin-6 Inhibitors