Role of macronutrients, vitamins and minerals in the aetiology of squamous-cell carcinoma of the oesophagus

Between 1992 and 1997 we conducted a case-control study of oesophageal cancer in 3 areas of northern Italy. Cases were 304 patients (29 women), ages 39-77 years (median age 60 years), with a first incident squamous-cell carcinoma (SCC) of the oesophagus. Controls were 743 patients (150 women), ages 35-77 years (median age 60 years), admitted for acute illnesses, unrelated to tobacco and alcohol, to major hospitals of the areas under surveillance. We derived estimates of daily dietary intake of 6 macronutrients, cholesterol, and 20 micronutrients or minerals from a validated food-frequency questionnaire, including 78 food groups and recipes and 15 questions on individual eating patterns. After allowance for age, gender, area of residence, education, body mass index, physical activity, smoking habit, alcohol consumption and energy intake, most micronutrients were inversely associated with oesophageal SCC risk. Highly significant associations emerged for monounsaturated fatty acids [odds ratio (OR) in highest vs. lowest intake quintile = 0.5]; carotene (OR = 0.3); lutein + zeaxanthin (OR = 0.4); vitamin C (OR = 0.4); and niacin (OR = 0.5). Only retinol appeared to be positively related to risk (OR = 1.9). The effect of the above nutrients, expressed as ORs, appeared to be similar in non-smokers and smokers, and non/light drinkers and heavy drinkers.