Photodynamic therapy of cancer of the esophagus using systemic aminolevulinic acid and a non–laser light source: a phase I/II study

Abstract

Background: Surgery is the mainstay for the treatment of carcinoma of the esophagus and is also considered to be effective for palliation of dysphagia. Patients who are unfit for surgery represent a difficult therapeutic problem. The goal of the present study was to evaluate the effects of photodynamic therapy by using systemic administration of 5-aminolevulinic acid and a non–laser light source on carcinoma of the esophagus. Methods: Patients were given 60 mg/kg 5-aminolevulinic acid orally. Twenty-four hours later gastroscopy was performed. After initial localization of the tumor with the use of white light, the light source was switched to the red light band at 100 J/cm 2 for 600 seconds. Gastroscopy was repeated at 48 hours and 7 days after the treatment. The degree of dysphagia was recorded before and 14 days after treatment. Results: Five patients with advanced nonresectable tumors or who were unfit for surgery were treated. Two patients had squamous cell carcinoma of the mid-esophagus and three had adenocarcinoma of the distal esophagus. Mild self-limiting photosensitivity was noted in all patients. Liver and renal function tests as well as hemoglobin level and white blood cell count were not affected by the treatment. Improvement of dysphagia was observed in four patients who had pretreatment dysphagia. The patient with the early stage of disease continued to eat a normal diet. Conclusions: Photodynamic therapy with systemic aminolevulinic acid as a photosensitizer and a non–laser light source is feasible and safe in advanced-stage esophageal cancer. It can be an effective modality for the relief of dysphagia in these patients.