[Incidence of cancer in the canton of Vaud. Etiologic hypotheses].

1,600 deaths are attributed to cancer in the Canton of Vaud, representing 23% of the total mortality. The incidence rates by sex for 12 cancer sites are compared, the data being taken from 3 cancer registries : Vaud, Geneva and the Saar (West Germany). The most important risk factors are mentioned for those sites with the highest rates. For men, cancers of the upper digestive and respiratory tract rank second, when the expectation of life associated with the age of onset of tumours of this site is taken into account. The sex ratio of males to females is particularly high. Some hypotheses, based on epidemiological observations, are formulated as to the causes of cancer of the upper digestive and respiratory tract.