In a consecutive autopsy series of 95 males, parenchymal hyperplastic nodules of clear cells occurred in 11.6% and liver cell dysplasia (LCD) in 7.4%. These two possible preneoplastic lesions never occurred together. Of the men, 50.5% had been alcoholics or had drunk more than an average of 80 g of alcohol daily, and 65.3% had been smokers, as established by interviewing a family member or a close friend of the deceased. Hyperplastic nodules of clear cells were found in association with liver cirrhosis (p less than 0.005), liver enlargement (p less than 0.025), and heavy alcohol consumption (p less than 0.05), and tended (n.s.) to be associated with smoking. The largest nodules of clear cells were found in nodular regenerative hyperplasia of the liver in a male who had used testosterone. In another case focal nodular hyperplasia coexisted. Hyperplastic nodules showed no association with the occurrence of cavernous hemangioma or benign bile duct tumors. Males with hyperplastic nodules of clear cells were significantly (p less than 0.01) younger (average 49.3 years) than those with LCD (average 61.1 years). Males with LCD were slightly (p less than 0.05) older, tended to have a small-sized liver, but were otherwise comparable with males without precursor lesions. The present results indicate that both hyperplastic nodules and liver cell dysplasia are common findings in male autopsy series comprising alcoholics and smokers. Hyperplastic nodules were associated with some of the predisposing factors of primary hepatocellular carcinoma.