Hepatocellular carcinoma after long-term tamoxifen therapy

We describe a case of hepatocellular carcinoma (HCC) after long term tamoxi fen therapy in a 71-year-old woman. The patient was prescribed tamoxifen fo r 12 years following right mastectomy and axillary node clearance for breas t carcinoma in 1985. In 1997, she complained of abdominal pain and fullness . An abdominal ultrasound scan showed lesions in the right lobe of liver wh ich were thought to be metastases. However, a biopsy showed primary HCC. St udies in rats suggest that tamoxifen is involved in hepatic carcinogenesis but studies in humans have failed to show any increased risk. However, thes e studies followed up patients for less than five years. An increased risk of HCC may not become apparent until after a decade or more of tamoxifen th erapy. In addition, HCC in tamoxifen treated patients may be under-reported since there may be reluctance to biopsy liver tumours which are assumed to be secondary carcinoma of the breast.