Distribution of primary cancers of the liver in the Province of Québec.

All records of primary liver cancer reported to the tumor registry of the Province of Québec from 1969 to 1972 were collected and were classified according to sex, age and place of residence. Men had higher incidence of primary liver cancer and the disease developed at an earlier age in men than it did in women. There was a noticeable difference in the number of cases in rural and urban areas, and a significant difference in the incidence in the 10 districts of the province. Cases in urban areas were clustered in a few industrialized cities. Our findings are in agreement with previous reports that show a relationship between primary cancer of the liver and the presence of chemicals in the environment.