NUTRITION AND LARYNGEAL-CANCER

The main etiologic factors of cancers of the larynx and hypopharynx ar e alcohol and tobacco, and their prevalence in different populations e xplains, to a large extent, the wide variations in incidence observed around the world. Besides these two main risk factors, however, diet a lso seems to play a role in determining the risk of these cancers. The re is consistent evidence that low consumption of fruit and vegetables is associated with higher risk, after statistical adjustment for alco hol and tobacco. Consumption of vegetable oils and fish and a moderate ly high polyunsaturated/saturated fatty acid ratio (P/S ratio) were re ported to be associated with reduced risk. Low intake of vitamin C, be ta-carotene and vitamin E were reported consistently to be associated with higher laryngeal cancer risk, but there was no clear evidence tha t these micronutrients are better predictors of cancer risk than the p rincipal food groups from which their intake levels were estimated, i. e., fruits, vegetables, vegetable oils, and fish. Given the overwhelmi ng role of tobacco and alcohol in the etiology of these cancers and th e extremely low incidence among nonsmokers/nondrinkers, the available studies provide no estimate of the role of diet in subjects not expose d to these factors. The evidence indicates, however, that, in the pres ence of tobacco and/or alcohol, low intake of fruit and vegetables may account for 25 to 50 percent of the cases among men.