[Mortality trends in Switzerland. 3. Tumors: 1921-1978].

Analysis of mortality from malignant tumours in Switzerland over the period 1921-1978 shows a considerable rise in the death rates from lung cancer and from malignant melanoma, and also an increase in death rates from cancers of pancreas, kidney, bladder, prostate, ovary and breast. Mortality from cancer of stomach (in the past the biggest killer of all cancers) has, on the other hand, drastically decreased; a decline is also observed in death rates from cancers of buccal cavity, oesophagus, gallbladder, rectum, larynx, uterus, and thyroid , as well as from malignant neoplasms of bone and skin (other than melanoma). Moreover, leukaemia mortality in children has markedly declined over the past twenty years. A number of factors are discussed which may have influenced the trend in death rates from the above malignant tumours, namely better diagnoses, changes in classification, new treatments, introduction of screening, and changes in population exposure to risk factors (tobacco, alcohol, irradiations, etc,).