Black tobacco, wine and mate in oropharyngeal cancer. A case-control study from Uruguay.

A case-control study of oral and pharyngeal cancer involving interviews with 108 cases and 286 controls was carried out in the University Hospital of Montevideo, Uruguay. The study was restricted to males and cases afflicted with lip, salivary gland and nasopharyngeal cancer were excluded. Point estimates of RR associated with smoking variables, alcohol variables, nutritional items and ingestion of hot infusions of the herb Ilex paraguariensis ('Mate') were obtained by logistic regression analysis. Dark tobacco smokers showed a RR 3.4 times higher than light tobacco users and heavy drinkers of wine displayed an OR of 17.2. Mate exposure showed a significant dose-response, after adjustment for age, tobacco and alcohol intake, with a fivefold increase in risk for heavy consumers. Joint exposure to black tobacco and wine displayed very high risks and no significant interactions were observed. The results suggest that the high rates of oropharyngeal cancer could be explained by the multiplicative effect of black tobacco smoking, wine drinking and mate ingestion.