Photodynamic therapy in cholangiocarcinoma

Cholangiocarcinoma (CCA) accounts for 3% of all gastrointestinal malignancy. Its incidence has significantly increased in the last few decades. Overall prognosis is poor in patients with a diagnosis of cholangiocarcinoma because disease has advanced at the time of presentation. Early diagnosis of the disease is essential, however, it is increasingly challenging despite the availability of different modalities given that the patient is typically asymptomatic in the early stages. Some options include adjuvant or neo-adjuvant chemotherapy, surgical therapy (i.e., biliary duct resection with or without hepatectomy, Whipples procedure, portal vein embolization, liver transplant). Surgical resection with clear margins is the only curative treatment option. Photodynamic therapy (PDT) with endoscopic or percutaneous biliary stent placement are now widely used in unresectable disease for palliative biliary decompression. It involves injecting of a photosensitizing agent 48hours prior to the laser treatment. Photosensitizing agent is retained by the malignant cells and they are then activated by the laser therapy which induces production of free radicals causing cell destruction. This chapter will discuss the particular details of the procedure including ideal use of PDT, the comparison between different photosensitizers, laser therapy delivery in explicit details, and benefits and complications from the therapy.