Bile duct cancer, also known as cholangiocarcinoma, is an uncommon cancer arising within the biliary tracts, bile-conveying structures, of the liver. The cancer first begins in the cells of the mucous glands that line the inside of the biliary tracts and cause these tracts to narrow, inhibiting the functions of the bile duct. In the U.S., the annual incidence of bile duct cancer is only one to two cases per 100,000 people. It also seems to be more common in males than females, and affects people over the age of 65.
Inflammatory Bowel Disease
Some people with chronic inflammatory bowel disease, or IBD, such as ulcerative colitis, also develop inflammation in the bile duct, a passage by which bile passes from the liver to the duodenum, which puts them at increased risk for bile duct cancer, says the Johns Hopkins Hospital. Ulcerative colitis is the inflammation and ulceration arising in the colonic mucosa, the lining of the large intestine and rectum, and is characterized by rectal bleeding, diarrhea and abdominal cramps.
Gallstones
The risk of developing bile duct cancer for a person with gallstones is 2 to 10 percent, according to the Johns Hopkins Hospitals. Gallstones are hard stone-like substances forming in the gallbladder or throughout the bile ducts of the liver and contain variable amounts of bile pigments and cholesterol. The pathogenetic relation between gallstones and bile duct is still unclear. However, it is believed that gallstones block the normal flow of bile from the liver to the small intestine, posing a risk for bile duct injury, adds the Johns Hopkins Hospitals.
Liver Fluke Infections
The most important clinical manifestation of liver fluke, any of various water-borne, parasitic worms that invade the bile duct epithelium of the liver, infections is cholangiocarcinoma, or bile duct cancer, notes the Macmillan Cancer Support. Bile duct carcinoma arising in association with liver fluke infection is most commonly seen is Asian and African countries, where people may become infected by one or more liver flukes, such as Clonorchis sinensis and Opisthorchis viverrini, by ingesting raw fish that is contaminated.
References
- Macmillan Cancer Support: Bile Duct Cancer (Cholangiocarcinoma)
- Johns Hopkins Hospitals: Cholangiocarcinoma: Causes
- MedlinePlus: Ulcerative Colitis
- The American College of Gastroenterology: Biliary Tract Disorders, Gallbladder Disorders and Gallstone Pancreatitis
- Johns Hopkins Hospitals: Cholangiocarcinoma: Introduction
