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A risk factor is anything that increases a person's chance of developing cancer. Although risk factors often influence the development of cancer, most do not directly cause cancer. Some people with several risk factors never develop cancer, while others with no known risk factors do. However, knowing your risk factors and talking about them with your doctor may help you make more informed lifestyle and health care choices.
The following factors may raise a person's risk of developing bile duct cancer:
Previous disease or irritation of the bile duct. Inflammation of the bile duct can be caused by ulcerative colitis or stones similar to gallstones. Diseases and conditions that increase the risk of bile duct cancer include:
- Primary Sclerosing Cholangitis (PSC), which is a rare inflammatory condition of the bile ducts with no known cause (see Statistics).
- Choledochal cyst, which is an abnormality a person is born with that causes a swollen area on the part of the bile duct outside the liver.
- Caroli's syndrome, which is an abnormality of the small bile ducts within the liver that a person is born with that increases the risk of infection and stones, like gallstones, forming in the liver.
- Cirrhosis, which is liver disease that can cause scarring or long-lasting irritation.
- Infection with liver flukes that invade the bile duct.
Age. Older adults are more likely to develop bile duct cancer.
Certain chemicals. Dioxins, nitrosamines, and polychlorinated biphenyls (PCBs) may cause bile duct cancer. In particular, people who work in rubber plants and automotive industries may be exposed to these chemicals.
Reducing Your Risk
Even though some people who have no risk factors develop bile duct cancer, there are ways to lower your individual risk of bile duct cancer.
- Avoid coming in contact with hazardous chemicals. Even though thorium dioxide (a chemical, previously used in x-ray examinations, associated with a high risk of developing bile duct cancer) has been banned from use, other hazardous chemicals are still available or found in the environment.
- Avoid alcohol abuse, which can lead to cirrhosis.
- If traveling in parts of the world where liver flukes are common, drink only purified water and foods that have been thoroughly cooked.


