Experience with pathological material from 150 women with liver tumors is reviewed. The features of liver cell adenoma and focal nodular hyperplasia are sufficiently different that the vast majority of the benign tumors can be easily subclassified. Although most occurred in women ingesting steroids, the wide usage of oral contraceptives makes it difficult to prove a causative role. Nineteen of the tumors were malignant and, to date, 12 of those patients have died of their disease. Since hepatomas are much more common than benign liver tumors, one must be even more circumspect in indicting steroids in their causation. In this group of women none had cirrhosis, whereas in the general population cirrhosis is a very common precedent lesion. Further investigation of estrogens and primary liver carcinoma would be timely.