Oral Contraceptives and Liver Tumours

Abstract

200 liver tumors in women taking birth control pills have been reported since 1973 when an association between these tumors and oral contraceptive use was 1st suggested. Most tumors have been benign showing histological characteristics of either hepatic cell adenoma or focal nodular hyperplasia. 1 survey found 543 cases of primary liver tumors reported between 1970-1975 of which 91.5% of those in males but only 43.8% of those in females were malignant. Overall 65% of the benign tumors among females were associated with oral contraceptive use but over 80% of benign tumor patients aged 20-30 were pill users. Further evidence of an association is the reported regression of liver tumors after cessation of pill use. However a study of 6 million people found only 1 benign hepatic tumor. Such conflicting results point to the need for an adequate epidemiological study to assess the frequency of tumors in users and nonusers compared with the frequency of oral contraceptive use in the female population. The duration of pill exposure and the type of estrogen used may be relevant to the development of benign liver tumors. Hemoperitoneum or hemorrhage in cases of focal nodular hyperplasia and tumor rupture in hepatic cell adenomas are significantly more frequent in pill users than nonusers. Most pill-associated tumors have been solitary and amenable to surgical resection with low mortality. While there is considerable evidence that oral contraceptive use plays a role in the development of hepatic cell adenomas and focal nodular hyperplasia there is less reason to believe the pill is involved in the pathogenesis of primary hepatocellular carcinoma. More research is needed to determine the oncogenic potential of oral contraceptives and the malignant potential of benign tumors.