Cholangiocarcinoma is a relatively rare neoplasm that is classified as an adenocarcinoma (a cancer that forms glands or secretes significant amounts ofmucins). It has an annual incidence rate of 1–2 cases per 100,000 in the Western world,^[1] but rates of cholangiocarcinoma have been rising worldwide over the past several decades.^[2]

Prominent signs and symptoms of cholangiocarcinoma include abnormal liver function tests, abdominal pain, jaundice, and weight loss. generalized itching,fever, and changes in color of stool or urine may also occur. The disease is diagnosed through a combination of blood tests, imaging, endoscopy, and sometimes surgical exploration, with confirmation obtained after a pathologistexamines cells from the tumor under a microscope. Known risk factors for cholangiocarcinoma include primary sclerosing cholangitis (an inflammatory disease of the bile ducts), congenital liver malformations, infection with the parasitic liver flukes Opisthorchis viverrini or Clonorchis sinensis, and exposure to Thorotrast (thorium dioxide), a chemical formerly used in medical imaging. However, most patients with cholangiocarcinoma have no identifiable specific risk factors.

Cholangiocarcinoma is considered to be an incurable and rapidly lethal malignancy unless both the primary tumor and any metastases can be fully resected (removed surgically). No potentially curative treatment yet exists except surgery, but most patients have advanced stage disease at presentation and are inoperable at the time of diagnosis. Patients with cholangiocarcinoma are generally managed - though never cured - with chemotherapy, radiation therapy, and other palliative caremeasures. These are also used as adjuvant therapies (i.e. post-surgically) in cases where resection has apparently been successful (or nearly so). Some areas of ongoing medical research in cholangiocarcinoma include the use of newer targeted therapies, (such as erlotinib) or photodynamic therapy for treatment, and the techniques to measure the concentration of byproducts of cancer stromal cell formation in the blood for diagnostic purposes.