CHOLANGIOCARCINOMA IMAGING MANAGEMENT

Cholangiocarcinoma
This is a malignant lesion arising in the wall of the bile duct. It is obviously easier to recognize from an ultrasound point of view when it occurs in and obstructs the common duct, as the subsequent dilatation outlines the proximal part of the tumour with bile. Cholangiocarcinoma may occur at any level along the biliary tree and is frequently multifocal. A cholangiocarcinoma is referred to as a Klatskin tumour when it involves the confluence of the right and left hepatic ducts. These lesions are often difficult to detect on both ultrasound and CT. They are frequently isoechoic, and the only clue may be the proximal dilatation of the biliary ducts. Although rare, the incidence of cholangiocarcinoma seems to be increasing and it is strongly associated with PSC, a disease of the biliary ducts which predominantly affects young men.

Multifocal cholangiocarcinoma may spread to the surrounding liver tissue and carries a very poor prognosis for long-term survival. In a liver whose texture is already altered by diffuse disease it may be almost impossible to identify these lesions before they become large. A pattern of dilated ducts distal to the lesion is a good clue.

Management of the patient with cholangiocarcinoma
These patients have a poor prognosis, as the lesions usually present with jaundice due to invasion and obstruction of the duct. They spread to surrounding tissues, including the portal vein and lymph nodes, metastasize to the liver, and can be multifocal, particularly with PSC. Staging of the disease is performed with CT or MRI. Endoscopic ultrasound can outline invasion into the biliary duct and laparoscopic ultrasound can pick up peritoneal or local spread.

Surgical resection of the tumour is becoming more successful in patients with single lesions. Palliation is frequently the only feasible option and the insertion of a stent, either percutaneously orendoscopically, to bypass the obstructing lesion and assist drainage of the liver will relieve the symptoms and often allows the patient to return home for some months.

Other treatment options, such as chemotherapy, have limited success, although transplantation is increasingly regarded as an option in some cases. Despite improvements in treatment, only a minority of patients survive beyond twelve months after the initial diagnosis.