People who have family members with bladder cancer do have a slightly increased risk of developing bladder cancer themselves. The increased risk is usually because people who live together are exposed to similar amounts of cigarette smoke, chemicals, pollutants, dietary risks, and other factors present in the environment.
In rare families, genetic abnormalities are associated with an increased risk of developing bladder cancer:
1. A mutation of a gene called the retinoblastoma gene (Rb1) can cause cancer of the eye in infants. The abnormal gene also increases the risk of developing bladder cancer.
2. Cowden disease, caused by mutations (changes) in a gene called PTEN, is linked to cancers of the breast and thyroid. People with this disease also have a higher risk of bladder cancer.
3. Hereditary nonpolyposis colorectal cancer (HNPCC) syndrome, also called Lynch syndrome, is mainly linked to colon and endometrial cancer. People with this syndrome have a slightly higher risk of bladder cancer.