Abstract
A primary hepatic tumour occurred in a 21-year-old woman who had been taking oral contraceptives for two years; she was treated by partial hepatectomy. Part of the neoplasm showed features suggestive of focal nodular hyperplasia, while the remainder had the histological characteristics of a well-differentiated hepatocellular carcinoma. This is the first report of malignant transformation of a tumour in a patient taking oral contraceptives.