Photodynamic therapy of Barrett's esophagus with dysplasia using systemic aminolevulinic acid and a non-laser light source. A phase I/II study

Background: Barrett's esophagus with dysplasia is a pre-malignant disease. Photodynamic therapy (PDT) involves the activation of a previously administered photosensitizing agent by red light, in order to cause cell destruction. Aim: To evaluate the effects of PDT using systemic 5-ALA on Barrett's esophagus with dysplasia. Methods: Patients were given orally 5-ALA 60 mg/kg and were subjected to PDT. Follow up was performed 48 h, 30 days and every 6 months for 18-30 months. Results: Eight patients (7 low-grade, 1 high-grade dysplasia) were treated. There were no major side effects. There was partial squamous regeneration in 3/8 patients 14 days after PDT. There was no evidence of dysplasia in 4/8 patients throughout the follow-up period. There were no long-term side effects such as strictures. Conclusion: PDT using systemic aminolevulinic acid (ALA) as a photosensitizer is feasible and safe in patients with Barrett's esophagus. Definitions of treatment parameters as well as long-term follow up are needed to establish treatment efficiency.