BACKGROUND: The changes of serum TNF-alpha, sTNFR, sIL-2R and sICAM-1 levels have been recently reported in some cancer patients but the clinical significance of these cytokines is not clearly established. To define the changes and clinical significance of these cytokines in patients with hepatocellular carcinoma (HCC), serum levels of TNF- alpha, sTNFR, sIL-2R and sICAM-1 were measured. METHODS: The serum levels of TNF-alpha, sTNFR, sIL-2R and sICAM-1 were measured before and after transarterial chemoembolization (TACE) by enzyme immunoassay in 20 patients with HCC and 10 adult healthy subjects as controls. These patients were divided into two groups, no response (NR, 14 cases) and partial response (PR, 6 cases) on the basis of changes of tumor size, new growth foci on the ultrasonographic or CT findings, and serum levels of alpha-fetoprotein. RESULTS: Serum levels of TNF-alpha, sTNFR, sIft-2R and sICAM-1 were significantly higher in all patients with HCC than in those of adult healthy controls (p<0.01). Serum levels of TNF-alpha after TACE tended in to be higher in comparison with those before TACE in the NR group (p<0.1), but those were not significantly different between before and after TACE in the PR group. Serum levels of sTNFR, sIL-2R and sICAM-1 were not significantly different between after and before TACE in both groups. CONCLUSIONS: These results suggest that serum levels of TNF-alpha, sTNFR, sIL-2R and sICAM:-1 in patients with HCC before therapy are significantly increased, compared with those of the control group, and the measurement of serum TNF-alpha levels may become useful in the diagnosis and monitoring of hepatocellular carcinoma in the future.