Risk factors for cancers of the tongue and the mouth
In Western countries, tobacco and alcohol are the principal risk factors for cancers of the oral cavity, including those of the tongue and the mouth. Dietary factors ate also believed to be important, but their exact roles have not been clearly established. Most epidemiologic studies have considered all cancers of the oral cavity together. The study de scribed here, conducted in northern Italy, evaluated cancers of the tongue and mouth separately.
One hundred two men with cancer of the tongue, 104 men with cancer of the mouth, and 726 male controls admitted to the same hospitals for diseases other than cancer were interviewed. The dietary questionnaire included information on 14 indicator foods as well as alcoholic and nonalcoholic beverages. Information was also collected on smoking habits and medical history.
Cigarette smoking and alcohol consumption were found to be strong risk factors for both cancer of the tongue and cancer of the mouth. High intakes of green vegetables, carrots, fresh fruits, coffee, and tea were associated with reduced risk of cancer at both sites. For all of these foods, the effects for mouth cancer appeared to be greater than those for tongue cancer. Whole-grain bread and pasta had similar, significant protective effects at both sites, while butter intake was associated with increased risk of cancer of the tongue only.
The findings confirm previous observations linking tobacco smoking and alcohol intake with increased risk of oral cancer. They are also consistent with earlier studies showing a significant protective effect of fresh fruits and vegetables. Some dietary factors may influence the risk of cancer of the tongue less strongly than the risk of cancer of the mouth.
