| Abstract: | Studies involving the role of OCs (oral contraceptives) in the etiology of benign and malignant liver tumors are reviewed. Although the number of reported cases is comparatively small (1 study cited an incidence rate of 1 case in 10,000 users after 5-10 years of contraceptive use), the available evidence strongly suggests that there is a relationship between the use of OCs and benign liver tumors. The acutal risk seems to be related to duration of usage, age of the woman, and type of contraceptive steroid used. 1 study showed the risk to be greater for those users who took pills with high doses of estrogens and progestogens. Analysis of liver tumors histologically showed the tumors among nonusers to be distributed among all the histologic types; there was a preponderance of hepatic cell adenomas (HCA) and focal modular hyperplasia (FNH) among users. Further evidence for an etiologic role for OCs in liver tumor formation can be derived from several cases of tumor regression or dormancy following OC discontinuance. Further etiologic studies should focus on other factors, e.g., female hormone balance, number of pregnancies, and liver disease. It is possible that FNH develops in women susceptible to hormonal stimulation. The malignant potential of benign tumors should also be studied. |
