Abstract
The presence of fat in the diet accelerates the production of hepatic tumors by p-dimethylaminoazobenzene (butter yellow), and when its quantity is very small, few are produced. Butter yellow with diets consisting in large part of rice, or with other diets with low protein content, causes nodular cirrhosis, but, rice substituted for sugar in a diet containing protein, fat, and butter yellow with adequate vitamins accelerates the production of tumors though the added rice is insufficient to induce nodular cirrhosis. Rice favors the production of hepatic tumors by agencies that are not yet explained. Butter yellow produces hepatic tumors in the absence of cirrhosis, but with diets that produce cirrhosis, the frequency of tumors and of their precursors, cystic ducts and cholangiofibrosis, increases with the severity of cirrhosis.