Bile Duct Cancer (Cholangiocarcinoma) - Symptoms & Causes

What is bile duct cancer (cholangiocarcinoma)?

Bile duct cancer, also known as cholangiocarcinoma, begins in the cells that line the inside of the bile ducts.

Bile ducts are thin tubes connecting your liver to your small intestine. They transport bile, which is produced by the liver, to help digest the fat we consume.

The bile duct system has several distinct parts. First, there are the intrahepatic bile ducts, found within the liver. This consists of small ductules, which merge into ducts, and then separate to become the left and right hepatic ducts.

The left and right hepatic ducts exit the liver, merging to form the common hepatic duct. The cystic (gallbladder) duct joins the common hepatic duct to form the common bile duct, which passes through the pancreas and joins with the pancreatic duct before emptying into the first part of the small intestine (duodenum).

In most countries, bile duct cancer is considered a rare type of cancer.

Types of bile duct cancer (cholangiocarcinoma):

There are several types of cholangiocarcinoma, based on where the cancer begins:

Intrahepatic bile duct cancers

These cancers begin in the small bile ducts inside the liver.

Perihilar or hilar bile duct cancers

These cancers start at the hilum, where the left and right hepatic ducts merge and exit the liver.

Distal bile duct cancers

These cancers occur further down the bile duct, closer to the small intestine.

What are the symptoms of bile duct cancer (cholangiocarcinoma)?

Symptoms of bile duct cancer include:

Abdominal pain on the right, just below the ribs
Dark urine
Fatigue
Fever
Itchy skin
Jaundice
Pale or light-coloured stools
Nausea and vomiting
Unexplained weight loss

What causes bile duct cancer (cholangiocarcinoma)?

It is unclear what causes bile duct cancer, but long-term (chronic) inflammation may contribute to its development, as inflammation can damage cells and lead to changes in its DNA, altering the way cells grow.

What are the risk factors for bile duct cancer (cholangiocarcinoma)?

These conditions are believed to be risk factors for bile duct cancer:

Parasitic infection of the bile duct
Abnormalities where the bile duct and pancreatic duct meet
Choledochal cyst disease
Chronic ulcerative colitis
Cirrhosis of the liver or chronic liver disease
Diabetes
Inflammatory bowel disease
Primary sclerosing cholangitis
Hepatitis B or C
Human immunodeficiency virus (HIV)
Non-alcoholic fatty liver disease
Obesity

Other factors which may play a role include:

Alcohol consumption, which can lead to liver cirrhosis
Exposure to certain toxins
Age, with most cases occurring over the age of 50

In some patients, the resulting tumour from bile duct cancer can obstruct the bile duct and cause infection of the bile drainage system (cholangitis).

Bile duct cancer may also lead to cirrhosis, causing scarring and destruction of liver cells, especially among patients with primary sclerosing cholangitis.