Photodynamic Therapy for High-Grade Dysplasia in Barrett's Esophagus

Photodynamic therapy followed by acid suppression with a proton pump inhibitor offers the potential of eradicating high-grade dysplasia in Barrett's esophagus, and the possible prevention of subsequent degeneration to invasive esophageal cancer. Areas of dysplasia are very heterogeneous and are often completely invisible to standard white light endoscopy. High-grade dysplasia may also be a multi-focal change and if so carries a greater chance of malignant degeneration. Therefore, treatment and eradication of the whole Barrett's segment is important. This remains a major advantage for photodynamic therapy. The principles that guide treatment are becoming clear. All the abnormal and Barrett's epithelium should be destroyed. Following photodynamic therapy, complete control of gastro-esophageal reflux, usually with proton pump inhibitors, is essential. The endpoint of treatment is re-epithelialization of the complete Barrett's segment with neo-squamous epithelium. Nevertheless, continued surveillance is still necessary since the phenotype expressed may still have malignant potential and cancer has occurred some time after apparently successful ablation. There is now the clear randomized evidence that Photofrin photodynamic therapy can eradicate high-grade dysplasia and prevent progression to invasive cancer.