Smoking and cancers of bladder and pancreas: risks and temporal trends

Mortality data from carcinomas of the pancreas (1941-75) and bladder (1941-70) in England and Wales were analyzed to study the association between cigarette smoking and these cancers. The analysis revealed that: a) The difference in male and female rates in these cancers is attributable to differences in smoking habits; b) the observed increase in mortality in these diseases is almost entirely due to a dramatic increase among smokers. The mortality rate among nonsmokers increased only slowly for carcinoma of the pancreas and actually fell for carcinoma of the bladder. This analysis, which is based on the total number of deaths in the population, yields estimates of relative risk associated with 20 pack-years of smoking of 1.6 and 3.0 for carcinomas of the pancreas and bladder, respectively. The proportion of deaths from carcinoma of the pancreas attributable to smoking increased from 25% in 1941-45 to 52% in 1971-75 in males and from 2 to 15% in females. The proportion of deaths from carcinoma of the bladder attributable to smoking increased form 53% in 1941-45 to 85% in 1966-70 in males and from 4 to 27% in females.