Risk factors for gallbladder cancer

A risk factor is something that increases the risk of developing cancer. It could be a behaviour, substance or condition. Most cancers are the result of many risk factors. Having gallstones is the most important risk factor for gallbladder cancer.

Gallbladder cancer increases with age. Most people diagnosed with gallbladder cancer are over age 65.

More women than men develop gallbladder cancer. Women have higher rates of gallstones and gallbladder inflammation, and this may contribute to their higher risk.

Gallbladder cancer rates are higher in certain countries and ethnic groups. Higher than average rates of gallbladder cancer occur in Israel, India, Latin America, eastern Asia and Europe. In North America, the number of people who get gallbladder cancer is low, but the rate of gallbladder cancer for Indigenous people of Canada and Native and Hispanic Americans is higher than average

Risk factors are generally listed in order from most to least important. But in most cases, it is impossible to rank them with absolute certainty.

Gallstones

Chronic inflammation

Choledochal cysts

Abnormalities of the pancreaticobiliary duct junction

Bacterial infection

Porcelain gallbladder

Overweight or obesity

Polyps

Thorotrast exposure

There is convincing evidence that the following factors increase your risk for gallbladder cancer.

The presence of gallstones in the gallbladder is called cholelithiasis. Gallstones are hard deposits of cholesterol and other substances. Having gallstones is a common condition and is more common in women. Having a history of gallstones is the most common risk factor for developing gallbladder cancer, but only a very small number of people with gallstones will develop gallbladder cancer.

Inflammation of the gallbladder is called cholecystitis. Chronic inflammation of the gallbladder can increase your risk of developing gallbladder cancer. Many risk factors for gallbladder cancer, including gallstones and bacterial infection, can cause inflammation. Primary sclerosing cholangitis, a disease of the bile ducts, can also cause chronic inflammation and a higher risk for gallbladder cancer.

Choledodal cysts are rare. They are also called congenital cystic disease of the biliary tree. They can develop if you are born with bile ducts that are larger than normal. Choledodal cysts can cause inflammation and an abnormal flow of bile in the bile ducts and gallbladder.

The pancreaticobiliary duct junction is the point where the pancreatic duct and the bile ducts join outside the first part of the small intestine (duodenum). An abnormality at this junction is called an anomalous junction of the pancreaticobiliary duct. It is rare and if you have it, you are born with it. It causes the pancreatic digestive juices to flow back into the bile ducts instead of into the small intestine. This can lead to chronic irritation of the gallbladder.

Chronic bacterial infections may cause chronic inflammation or irritation of the gallbladder and increase the risk of gallbladder cancer. These infections include:

Salmonella typhi (S. typhi) causes typhoid fever. Sometimes you can have the bacteria in your body but not have any symptoms. People in this carrier state often get gallstones, which may contribute to a higher risk of gallbladder cancer.

Helicobacter bilis (H. bilis) and Helicobacter pylori (H. pylori) have been linked to a higher risk of gallbladder cancer. Helicobacter infection may lead to gallstones and chronic inflammation.

Porcelain gallbladder is an uncommon condition. Calcium builds up on the walls of the gallbladder, causing it to harden (calcify). It may be caused by chronic inflammation of the gallbladder, usually because of gallstones.

Overweight or obesity is a risk factor for gallbladder cancer. Obesity is linked with gallstones, the most common risk factor for gallbladder cancer.

A gallbladder polyp is a growth on the inside lining of the gallbladder. Most polyps are non-cancerous. Polyps larger than 1 cm are more likely to become cancerous. Cancerous gallbladder polyps are found more often in older people.

Thorotrast (thorium dioxide) is a contrast medium that was used for imaging tests in the past. Studies show that people who were injected with Thorotrast have a higher risk for gallbladder cancer.

The following factors have been linked with gallbladder cancer, but there is not enough evidence to show for sure that they are risk factors. More research is needed to clarify the role of these factors for gallbladder cancer.

• family history
• diabetes
• number of pregnancies

To make the decisions that are right for you, ask your healthcare team questions about risks.