Dietary indicators of laryngeal cancer risk.

The relationship between frequency of intake of a selected number of indicator foods and the risk of laryngeal cancer was investigated in a case-control study conducted in northern Italy on 110 males with histologically confirmed cancer of the larynx and 843 controls in the hospital for acute, nonneoplastic or respiratory diseases. Significant direct associations were observed with tobacco [relative risk (RR) = 5.8 for current versus never smokers] and alcohol (RR = 2.3 for the upper versus lower tertile of consumption), while the frequency of consumption of three food items was inversely related with laryngeal cancer risk. These were fish (RR = 0.6 for the upper tertile), green vegetables (RR = 0.4), and fresh fruit (RR = 0.3). Multiple logistic regression analysis, including simultaneously major nondietary covariates and various food items, suggested that the strongest and most consistent protective effect was given by fruit. These findings can be generally interpreted as an indication that a "poorer" diet is related to a raised risk of laryngeal cancer, although the confirmed observation that fruit appears to be the main protective dietary factor against cancers of the upper respiratory and digestive tract is of potential interest and may suggest useful etiological clues. Dietary findings were similar in different strata of alcohol and tobacco consumption.