Bladder cancer is the ninth most common cancer worldwide, with 429 793 incident cases and 165 068 deaths estimated to have occurred in 2012.
The EPIC Bladder Cancer Working Group aims to study the effect of diet, micronutrients, lifestyle factors such as smoking, alcohol consumption, physical activity, use of exogenous hormones, and other personal and lifestyle characteristics on the risk of bladder cancer. In addition, the group is conducting studies on the role of genetic susceptibility (genome-wide association studies) and gene—environment interactions, as well as studies on biomarkers of susceptibility.
Some of the findings from recent publications of the group indicate that:
- The strong association between tobacco smoking and bladder cancer shown in several studies has also been found in EPIC, where it was possible to examine smoking patterns in more detail, showing an increased bladder cancer risk with smoking intensity and duration, and even among occasional smokers, as well as an increased risk with environmental tobacco smoke exposure in childhood.
- The association between dietary components and bladder cancer has been investigated extensively in EPIC, focusing on vegetable and fruit consumption and intake of meats and associated components, haem iron, nitrosamines, and heterocyclic aromatic amines. The studies have shown no strong effect of these dietary components in bladder cancer etiology. However, among a specific genetically defined subgroup; the rapid NAT2 genotype, increased risk of bladder cancer with meat intake was found.
- The association between fluid intake and bladder cancer has been examined in several studies under the hypothesis that direct contact of bladder cells with urinary carcinogens may relate to the development of bladder cancer, and that a high consumption of fluids may dilute the urine and hereby reduce contact time between bladder cells and carcinogens. Results from previous studies have been inconsistent. Examination of the association in EPIC showed that there was no association between total fluid intake and bladder cancer, for neither high-risk nor low-risk tumours.