Risk factors for hepatocellular carcinoma in northern Italy.

The role of socio-demographic factors, lifestyle habits and selected dietary factors on the risk of hepatocellular carcinoma was evaluated in a hospital-based case-control study conducted in Northern Italy on 151 patients with hepatocellular carcinoma and 1,051 controls in hospital for acute, non-neoplastic or digestive conditions, unrelated to any of the known or potential risk factors for primary liver cancer. There were significant inverse relationships with levels of education and social class (relative risk, RR = 1.9 and 2.4 for lower vs. upper categories), and positive associations with clinical history of hepatitis (RR = 3.5, 95% confidence interval = 2.0-6.0) or liver cirrhosis (RR = 15.6, 95% CI = 8.3-29.4). The relative risk was not elevated in smokers and light or moderate alcohol drinkers, but the point estimate was above unity among heavy drinkers (RR = 1.5, 95% CI = 1.0-2.4). Among 14 food items considered, including important sources of vitamin A, protein and fats in the Italian diet, 5 were inversely and significantly related to liver cancer risk. This suggests that a diet deficient in several aspects may be related to hepatocellular carcinoma.