Diet and bladder cancer: a case-control study

To investigate possible relationships between diet and risk for bladder cancer in Serbia, the hospital-based case-control study was carried out. This study included 130 newly diagnosed bladder cancer patients and the same number of controls matched by sex, age (%+/-%2 years) and type of residence (rural or urban). Dietary information was obtained by using a food frequency questionnaire. Initial case-control comparisons were based on tertiles of average daily intake of control group. The odds ratios (ORs) were computed for each tertile, with the lowest tertile defined as the referent category. All variables (food items) significantly related to bladder cancer were included in multivariable logistic regression analysis. According to this analysis, risk factors for bladder cancer appeared to be consumption of liver (OR=6.60, 95%CI=1.89-23.03), eggs (OR=3.12, 95%CI=1.10-8.80), pork (OR=2.99, 95%CI=1.16-7.72), and pickled vegetable (OR=3.25, 95%CI=1.36-7.71). A protective effect was found for dietary intake of kale (OR=0.21, 95%CI=0.06-0.73), cereals (OR=0.19, 95%CI=0.06-0.62), tangerines (OR=0.21, 95%CI=0.07-0.68), cabbage (OR=0.27, 95% CI=0.11-0.68), and carrots (OR=0.15, 95%CI=0.05-0.41). The study indicated a potentially important role for dietary fat and pickled vegetables in bladder carcinogenesis. An inverse association was recorded between consumption of fruits, vegetables and cereals, and the development of bladder cancer.