Serum interleukin-18: does it have a role in the diagnosis of hepatitis C virus related hepatocellular carcinoma?

Background And Study Aims: Early diagnosis of hepatocellular carcinoma (HCC) is the only hope for cure. Although the role of alpha foetoprotein (AFP) in the diagnosis of advanced HCC is well recognised, at least one-third of cases will be missed unless another diagnostic tool is used. Increased levels of circulating interleukin-18 (IL-18) have been observed in patients with several cancer types and were described in patients with chronic hepatitis. The aim of this study is to assess the role of serum IL-18 level in the diagnosis of hepatitis C virus (HCV)-related HCC.

Patients And Methods: A total of 75 subjects categorised into four groups, including 25 patients with HCV-related HCC and AFP above 200ng/ml, 25 patients with HCV-related HCC and AFP below 200ng/ml, 15 patients with HCV-related chronic liver disease and 10 healthy controls, were enrolled. HCC was diagnosed according to guidelines of the American Association for the Study of Liver Diseases. AFP and IL-18 were assessed in all subjects.

Results: AFP and IL-18 levels are significantly higher in patients with HCC than in disease control and healthy control subjects. IL-18 level is not correlating with the size or the number of hepatic focal lesions neither with the presence of lymphovascular invasion or abdominal lymphadenopathy. The best cut-off value of IL-18 for the diagnosis of HCC is 500pg/ml with 84% sensitivity and 86.7% specificity and the area under receiver operating characteristic curve is 0.675.

Conclusion: Serum IL-18 level is a suitable marker for the diagnosis of HCV-related HCC complementary to AFP, especially in cases with AFP level less than the diagnostic value.