title: Marked elevation of serum interleukin-6 in patients with cholangiocarcinoma: validation of utility as a clinical marker.
abstract: OBJECTIVE
  To determine if the serum level of interleukin-6 (IL-6) was elevated in patients with hepatic malignancies or correlated with radiologic tumor burden.
  
  
  BACKGROUND
  High serum levels of IL-6 signify an adverse prognosis in many patients with cancer. IL-6 is a growth factor for bile duct epithelium.
  
  
  METHODS
  Using bioactive and enzyme-linked immunosorbent assays, serum level of IL-6 was measured in 35 healthy adults and in 60 patients presenting for definitive management of cholangiocarcinoma (CC) (15 patients), hepatocellular carcinoma (HCC) (14), metastatic colorectal cancer (MCRC) (26), and benign biliary disease (BBD) (5). Patients with clinical conditions known to raise the serum level of IL-6 were excluded. Tumor burden was calculated from concurrent computed tomography scans. IL-6 levels were measured 2 weeks after resection in 3 CC patients. Secretion of IL-6 was examined in 3 human CC cell lines.
  
  
  RESULTS
  An elevated level of bioactive IL-6 was detected in every patient with CC and in 13 of 14 patients with HCC, 14 of 26 patients with MCRC, 2 of 5 patients with BBD, and 3 of 35 healthy adults. Median and mean levels of bioactive IL-6 were higher in CC than in other neoplasms (p < 0.026) and for all tumor groups differed from healthy adults (p < or = 0.026). IL-6 level was elevated more often in primary than in secondary liver neoplasms (p = 0.02), distinguished patients with CC or MCRC from BBD (p = 0.014 and 0.031, respectively), correlated with tumor burden in CC (p < 0.001), and dropped sharply after CC resection. CC line SG231 secreted bioactive IL-6.
  
  
  CONCLUSIONS
  In selected patients, a high serum level of IL-6 marks patients with CC and correlates with tumor burden both before and after resection. IL-6 levels are elevated in patients with other liver neoplasms and may distinguish patients with hepatic malignancies from those with benign disease.
authors.affiliation: Department of Surgery, University of Pittsburgh, Pennsylvania, USA.
authors.forename: J S
authors.initials: JS
authors.lastname: Goydos
authors.forename: A M
authors.initials: AM
authors.lastname: Brumfield
authors.forename: E
authors.initials: E
authors.lastname: Frezza
authors.forename: A
authors.initials: A
authors.lastname: Booth
authors.forename: M T
authors.initials: MT
authors.lastname: Lotze
authors.forename: S E
authors.initials: SE
authors.lastname: Carty
mesh_terms: D000328:Adult; D001650:Bile Duct Neoplasms / Q000097:blood*; D001653:Bile Ducts, Intrahepatic; D014408:Biomarkers, Tumor / Q000097:blood*; D018281:Cholangiocarcinoma / Q000097:blood*; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D008297:Male
chemical_list: D014408:Biomarkers, Tumor; D015850:Interleukin-6