Cancer of the larynx/hypopharynx, tobacco and alcohol: IARC international case-control study in Turin and Varese (Italy), Zaragoza and Navarra (Spain), Geneva (Switzerland) and Calvados (France).

A case-control study on larynx and hypopharynx cancer was carried out in 6 populations including the city of Turin and the province of Varese (Italy), the provinces of Navarra and Zaragoza (Spain), the canton of Geneva (Switzerland), and the département of Calvados (France). This report presents an analysis of the risk associated with alcohol and tobacco consumption based on 1,147 male cases and 3,057 male population controls. Special attention was given to the study of the risk at various sites of larynx and hypopharynx. The effect of tobacco is similar for all sites and the risk associated with ever smoking is on the order of 10. The risks from alcohol drinking depend on site. They are similar for epilarynx and hypopharynx (RR = 4.3, for more than 80 g/day) and lower for endolarynx (RR = 2.1, for more than 80 g/day). For all sites the risk decreases after quitting (RR = 0.3 after 10 years); exclusive use of filter cigarettes is protective (RR = 0.5 relative to smokers of plain cigarettes only) as is exclusive use of blond tobacco (RR = 0.5 relative to smokers of black tobacco only). Inhalation increases the risk of endolaryngeal cancer but not that of hypopharynx or epilarynx. The relative risks for joint exposure to alcohol and tobacco are consistent with a multiplicative model.