Description:
If cancer develops in the biliary tract, it may prevent bile flowing from the liver to the intestine. Early cancers are often asymptomatic but as the disease advances patients may experience symptoms such as jaundice, itchy skin, abdominal discomfort, loss of appetite, weight loss and fever.
Treatment options depend largely on the stage, size, position and type of the cancer. Bile duct cancer is not usually diagnosed before the symptoms of biliary obstruction occur, by which time the cancer may be too advanced for curative surgical resection. The standard options for palliative treatment include surgical bypass of the bile duct or the insertion of a stent using surgical, endoscopic or percutaneous techniques.
Photodynamic therapy (PDT) produces localised tissue necrosis by applying a photosensitising agent and then exposing the area to laser light of an appropriate wavelength. A photosensitising agent is used that preferentially accumulates in the tumour tissue rather than normal tissue.
Photodynamic therapy is usually administered in conjunction with a biliary stenting procedure. The photosensitising agent is injected intravenously and photoactivation is performed approximately 48 hours later. This is done by inserting a laser through a catheter situated close to the tumour or by placing the laser directly across the tumour. Patients remain in the dark for about 3 days after injection and are then gradually readapted to light.
|
