Photodynamic therapy for unresectable cholangiocarcinoma

Cholangiocarcinoma (CC) is a rare primary malignancy of the biliary tract with a dismal prognosis. Curative resection can only be applied to a small proportion of early diagnosed patients. Palliative biliary drainage by either percutaneous or endoscopic insertion of endoprostheses improves quality-of-life by reducing pruritis, cholangitis, and pain, but has been reported to improve survival time only slightly. Photodynamic therapy (PDT) is a relatively new local, minimally invasive palliative strategy for unresectable CC. PDT uses a photosensitive molecule that accumulates in proliferating tissue such as tumors. Activation of the photosensitizer by use of light of a specific wavelength generates reactive oxygen species leading to selective tumor-cell death. After initial feasibility studies and promising prospective phase II studies, results from two prospective randomized controlled trials comparing PDT after endoprostheses insertion with endoprostheses alone for patients with unresectable CC have been published. One study resulted in dramatically prolonged median survival in the PDT group (493 days) compared with the non-PDT group (98 days) (P < 0.0001), and significantly improved performance status (PS) in the PDT group. A second study with high baseline patients' PS confirmed the benefit of PDT for survival (630 days in the PDT group compared with 210 days for endoprostheses alone, P < 0.01). The procedures were generally well tolerated. PDT has also been reported to have a favorable outcome as adjuvant and neoadjuvant therapy for CC. Although accumulated data and local expertise are limited, PDT can be regarded as a standard palliative therapy for unresectable CC.