MARKED ELEVATION OF SERUM INTERLEUKIN-6 IN PATIENTS WITH CHOLANGIOCARCINOMA - VALIDATION OF UTILITY AS A CLINICAL MARKER

Objective To determine if the serum level of interleukin-6 (IL-6) was elevated in patients with hepatic malignancies or correlated with radi ologic tumor burden. Summary Background Data High serum levels of IL-B signify an adverse prognosis in many patients with cancer. IL-6 is a growth factor for bile duct epithelium. Methods Using bioactive and en zyme-linked immunosorbent assays, serum level of IL-6 was measured in 35 healthy adults and in 60 patients presenting for definitive managem ent of cholangiocarcinoma (CC) (15 patients), hepatocellular carcinoma (HCC) (14), metastatic colorectal cancer (MCRC) (26), and benign bili ary disease (BED) (5). Patients with clinical conditions known to rais e the serum level of IL-6 were excluded. Tumor burden was calculated f rom 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 H CC, 14 of 26 patients with MCRC, 2 of 5 patients with BED, and 3 of 35 healthy adults. Median and mean levels of bioactive IL-8 were higher in CC than in other neoplasms (p < 0.026) and for all tumor groups dif fered from healthy adults (p less than or equal to 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 BED (p = 0.014 and 0.031, respectively), correlated with tumor burden in CC (p < 0.00 1), and dropped sharply after CC resection. CC line SG231 secreted bio active IL-6. Conclusions In selected patients, a high serum level of I L-8 marks patients with CC and correlates with tumor burden both befor e and after resection. IL-6 levels are elevated in patients with other liver neoplasms and may distinguish patients with hepatic malignancie s from those with benign disease.