Dietary factors in the epidemiology of cancer of the larynx.

Interviews were carried out with 374 male patients at Roswell Park Memorial Institute with cancer of the larynx and 381 controls with diseases other than of the digestive or respiratory system and other than neoplasms. As have other investigators, the authors found a high risk associated with smoking as well as a risk associated with alcohol ingestion. In addition, the study found that males ingesting low amounts of vitamin A in their diet had approximately twice the risk of those ingesting large amounts. The same was true for vitamin C. All of these relationships were significant, and risk increased in dose-response fashion with decreases in ingestion of the above-mentioned dietary constituents. When the risks associated with vitamins A and C were examined controlling for smoking and drinking, the risk enhancement associated with low ingestion persisted. The findings on nutrients are consistent with results of studies on animals and tissue cultures. Nevertheless, the sparse epidemiologic replication, the difficulties with the methods, and the complexity of the field demand substantial further inquiry on these relationships.