The Treatment Of Esophageal Cancer By Vascular-Targeted Photodynamic Therapy (Vtp) Using Orthotopic Rat Model.

91 Background: Vascular targeted photodynamic therapy (VTP) based on local sensitization of circulating WST11, a water-soluble derivative of Pd-bacteriochlorophyll, enables effective focal ablation of solid tumors. Highly toxic oxygen radicals are produced in the vascular lumen upon illumination with near infra-red light (755nm), leading to irreversible occlusion of tumor feeding arteries and veins. WST11 clears rapidly from the circulation and does not accumulate in the body, providing high level of safety and minimizing adverse effects. WST11-VTP completed Phase II clinical trials in USA and Phase III in Europe for the treatment of early localized prostate cancer as a first line monotherapy with above 80% complete response rate. Here we evaluate its’ safety and efficacy for the treatment of esophageal cancer aiming at development of clinically translatable treatment protocol. Methods: We developed an orthotopic model in which esophageal cancer cells are implanted in the mid esophagus using endoscopy gui...