Bladder and kidney cancers.

The major factor contributing to the increase in incidence of both renal and urothelial cancers has been improved detection rates. To a considerable extent, this accounts for the difference between the trends in incidence and mortality since, on the whole, the efficacy of treatment has improved only slowly. In the case of renal parenchymal cancer, the true burden of disease is rising almost everywhere, probably reflecting changes in standard of living, perhaps chiefly diet, although there will be some contribution from smoking. Where the increase in bladder cancer is not artefactual, it can be attributed in large part to smoking and perhaps to increasing industrial exposure in some localities. Trends in incidence and, to a greater degree, mortality for urothelial cancer are likely to improve substantially with implementation of policies of prevention (reduction in smoking, improvements in industrial hygiene), earlier detection (eg with monoclonal antibodies) and treatment (immunotherapy). No such optimism can be held with respect to renal parenchymal cancer, which is set to become one of the major cancers of affluent societies unless its aetiology becomes known and can be addressed.