Twenty-three patients (16 male, seven female) with hepatocellular carcinoma (HCC) were treated by hepatic arterial infusion (HAI) of mitoxantrone every 4 weeks. At each treatment, a catheter was inserted percutaneously into the main hepatic artery via the femoral artery under image intensification. Treatment consisted of a 24-hour continuous HAI of mitoxantrone, 6 mg/m2/d X 3 (eight patients) or 10 mg/m2/d X 3 (14 patients) without heparin. Eight patients had only one infusion, nine patients four infusions, five patients three infusions, two patients two infusions, and one patient five infusions. A partial response was seen in six patients, with a median duration of 20 weeks (range, 18 to 38 weeks). Five patients achieved stable disease, with a median duration of 20 weeks (range, 11 to 42 weeks). The median survival of the overall group was 22 weeks. Survivals of responding, stable, and nonresponding patients were 32 weeks, 24 weeks, and 9 weeks, respectively. Complications of catheter placement included asymptomatic dissection of the hepatic artery (one patient), and asymptomatic thrombosis of the hepatic artery (five patients). Three patients experienced mild nausea and vomiting, and six patients had mild to moderate alopecia. Granulocytopenia was frequent at both dose schedules. The granulocyte nadir was greater than 1,000/microL in 34% of evaluable courses, 500 to 1,000/microL in 32%, and less than 500/microL in 34% of courses. Two patients developed neutropenia-associated fever. A platelet nadir below 100,000/microL was seen after only 10% of courses, and only two patients had platelets below 50,000/microL. Seven patients received doxorubicin after progression on mitoxantrone. Four received systemic doxorubicin, 50 mg/m2, and three HAI of doxorubicin, 25 mg/m2, for three days. Two patients achieved partial response (18 weeks and 32 weeks) to HAI doxorubicin. Mitoxantrone has activity in HCC and is well tolerated when administered by HAI. It is not entirely cross-resistant with doxorubicin.