PHOTODYNAMIC ABLATION OF HIGH-GRADE DYSPLASIA AND EARLY CANCER IN BARRETTS-ESOPHAGUS BY MEANS OF 5-AMINOLEVULINIC ACID

Background & Aims: The first therapeutic experiences with the conventi onal photosensitizer dihematoporphyrinester in the treatment of Barret t's esophagus show the curative potential of photodynamic therapy (PDT ). The aim of this study was to test 5-aminolevulinic acid (5-ALA)-ind uced protoporphyrin IX, a photosensitizer with a high mucosa specifici ty without phototoxic side effects on the skin, as a new form of PDT. Methods: Thirty-two patients (mean age, 68.5 years) with histologicall y proven high-grade dysplasia (n = 10) and mucosal cancer (n = 22) in Barrett's esophagus were treated. Four to 6 hours after oral ingestion of 5-ALA (dose, 60 mg/kg body wt), irradiation was conducted with a d ye laser system (635 nm) with a light dose of 150 J/cm(2). The patient s received 20-80 mg omeprazole daily after PDT. Results: High-grade dy splasia was eradicated in all patients (10 of 10), and mucosal cancer was eliminated in 17 of 22 patients (77%) at a mean follow-up of 9.9 m onths (range, 1-30 months). All tumors less than or equal to 2 mm in t hickness were completely ablated (17 of 17). The method-related mortal ity and morbidity was 0%. Conclusions: Severe dysplasia and thin (less than or equal to 2 mm) mucosal cancer of Barrett's esophagus can be c ompletely ablated. PDT might offer a minimally invasive treatment moda lity as an alternative to esophagectomy.