BACKGROUND. The objective of the current study was to identify patient and disease related factors that influence response and survival for patients with unresectable hepatocellular carcinoma (HCC) who received a systemic combination chemotherapy consisting of cisplatin, alpha-interferon, doxorubicin, and 5-fluorouracil (PIAF). METHODS, From July 1996 to February 1999, 149 patients with unresectable HCC were treated with PIAF: cisplatin (20mg/m(2) intravenously, Days 1-4), doxorubicin (40mg/m(2) intravenously, Day 1), 5-fluorouracil (400mg/m(2) intravenously, Days 1-4), and alpha-interferon (5MU/m(2) subcutaneously, Days 1-4), once every 3 weeks up to a maximum of six cycles. Univariate and multivariate analyses of patient and disease characteristics were used to identify factors predicting response and survival. RESULTS. The objective response rate according to conventional criteria was 16.8% (complete response in 3 out of 149 patients, or 2%, 95% confidence interval [CI] 0-4.3%; partial response in 22 out of 149 patients, or 14.8%, 95% CI 9-20%). The median survival time was 30.9 weeks (95% CI 22.1 to 40). Significant independent predictors of an objective response were: absence of cirrhosis (P = 0.006), low bilirubin level (P = 0.006), and positive hepatitis C serology (P = 0.025). The following factors were related to a shorter survival time: high Okuda stage (P = 0.001), vascular involvement (P = 0.018), and cirrhosis (P = 0.008). Good risk patients (absence of cirrhosis and total bilirubin less than or equal to 0.6mg/dL) had an objective response rate of 50%. CONCLUSIONS. Patients with unresectable HCC who also have normal total bilirubin and non-cirrhotic livers have a better chance of response and prolonged survival after treatment with systemic PIAF. (C) 2002 American Cancer Society.