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Development of photodynamic therapy for Barrett's esophagus

High grade dysplasia in columnar lined (Barrett's) oesophagus is a premalignant condition. An oesophageal resection in these patients carries significant risks and is associated with considerable morbidity in often asymptomatic patients. Endoscopic destruction of these areas using photodynamic therapy (PDT) offers obvious benefits for patient care and treatment costs. An oesophageal dilator developed for patient endoscopic treatments is described. Experiments were performed to obtain information on the interaction of laser light with the oesophageal tissue. Fluorescence microscopy of tissue biopsies provided information on the distribution of aminolevulinic acid (ALA) induced protoporphyrin IX (PpIX) photosensitization. Six clinical treatments were performed, the results of which are reported.