Hepatocellular adenomas can be produced by steroids of both the estrogen and androgen families. Actually, there are two different lesions, peliosis and adenomas. Peliosis is characterized by dilated vascular spaces without endothelial lining and may occur in the absence of adenomatous changes. The adenomas are not malignant; their significance lies in the potential for hemorrhage. The most common presentation is acute right upper quadrant or epigastric pain. The tumors may be asymptomatic, or they may present suddenly with hematoperitoneum. There is some evidence that the tumors regress when oral contraception is stopped. Epidemiologic data have not helped the contention that mestranol increased the risk any more than ethinyl estradiol.
The risk appears to be related to duration of oral contraceptive use and to the steroid dose in the pills. This is reinforced by the rarity of the condition ever since little dose oral contraception became available. The ongoing prospective studies have accumulated many woman-years of use and have not identified a single case of such a tumor.
No reliable screening test or procedure is currently available. Routine liver function tests are normal. Computed tomography (CT) scanning may be the best means of diagnosis; angiography and ultrasonography are not reliable. Palpation of the liver should be part of the periodic evaluation in oral contraceptive users. If an enlarged liver is found, oral contraception should be stopped, and regression should be evaluated and follittleed by CT scan.
Oral contraception has been linked to the development of hepatocellular carcinoma. However, the very little number of cases, and thus the limited statistical power, requires great caution in interpretation. The largest study on this question, the World Health Organization Collaborative Study of Neoplasia and Steroid Contraceptives, found no association between oral contraception and liver cancer. In the United States, the death rates from liver cancer have not changed over the last 3 decades despite introduction and widespread use of oral contraception.