RATIONALE: Estrogen can stimulate the growth of cancer cells. Hormone therapy using tamoxifen may fight liver cancer by blocking the absorption of estrogen. It is not yet known whether receiving tamoxifen is more effective than no further therapy in treating patients with primary liver cancer.

PURPOSE: Randomized phase III trial to compare high-dose tamoxifen with no further treatment in treating patients with liver cancer that cannot be surgically removed.

OBJECTIVES: I. Assess the therapeutic role of tamoxifen in patients with inoperable hepatocellular carcinoma in terms of overall survival and quality of life.

OUTLINE: This is a randomized, double blind, placebo controlled study of tamoxifen. Patients are randomized to one of 3 treatment arms. Arm I: Patients receive placebo orally twice daily for one year. Arms II and III: Patients receive tamoxifen, at 1 of 2 different doses, orally twice daily for one year. Quality of life is assessed before treatment and then monthly thereafter. Patients are followed monthly until death.

PROJECTED ACCRUAL: This study will accrue 300 patients.

DISEASE CHARACTERISTICS: Histologically or radiologically confirmed inoperable hepatocellular carcinoma Serum alfa-feto protein level at least 500 ug/L OR Positive lipiodol uptake

PATIENT CHARACTERISTICS: Age: 10 to 90 Performance status: ECOG 0-3 Life expectancy: Not specified Hematopoietic: Not specified Hepatic: Not specified Renal: Creatinine less than 1.7 mg/dL Other: No encephalopathy

PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: No prior chemoembolization therapy for disease No prior systemic chemotherapy for disease Endocrine therapy: Not specified Radiotherapy: Not specified Surgery: No prior surgery for disease Other: No prior percutaneous injection