Background: Bladder cancer is three to five times more frequent in men than in women, and hence only a few studies have focused only on females.
Methods: A case-control study was conducted between 1985 and 1992 in two areas of northern Italy, and included 110 women with histologically confirmed bladder cancer and 298 controls, admitted to the same network of hospitals of cases for acute, non-neoplastic, non-urinary or genital tract diseases. Multivariate odds ratios (ORs) were computed using unconditional multiple logistic regression.
Results: Compared to never smokers, current smokers (OR = 2.87) had significantly elevated risks of bladder cancer. High intake of vegetables was inversely related to the disease (OR = 0.32), while history of occupation in chemical, dyes/paints or pharmaceutical industry (OR = 3.01) was directly associated to risk of bladder cancer. The OR was 3.29 for ever use of menopause hormone replacement therapy.
Conclusions: This study confirms that cigarette smoking is the prominent risk factor for bladder cancer in women as in men, with similar relations in both sexes. It also confirms that selected occupational factors are related to bladder cancer risk, and supports a favourable role of vegetables. The apparent relation with hormone replacement therapy in menopause needs interpretation and further investigation.