Hyperbaric oxygen and photodynamic therapy in the treatment of advanced carcinoma of the cardia and the esophagus

Background and Objective: The photochemical reaction of photodynamic therap y (PDT) depends on the presence of molecular oxygen, Because of anoxic regi ons in tumor tissue and vascular shutdown during PDT, the efficiency is lim ited. Therefore, the use of hyperbaric oxygen, which increases the oxygen i n tumor tissue, as well as the amount of singlet oxygen, may enhance the ef ficiency of PDT. Study Design/Materials and Methods: After diagnostic work-up, photosensitiz ation was carried out with a hematoporphyrin-derivate 2 mg/kg body weight 4 8 hours before PDT, The light dose was calculated as 300 J/cm of fiber tip. Twenty-three patients were treated by PDT alone and 29 patients received P DT under hyperbaric oxygen at a level of two absolute atmospheric pressures . Results: Improvement regarding dysphagia and stenosis-diameter could be obt ained in both treatment arms with no significant difference (P = 0.43 and P = 0.065, respectively). The tumor length also decreased in both groups and showed a significant difference in favour of the PDT/HBO group (P = 0.002) , The mean overall survival was 11.3 months, The mean survival time for the PDT group was 8.7 months and for the PDT/HBO group 13.8 months (P = 0.021) . Conclusion: According to this pilot study, combined PDT/HBO represents a ne w approach in the treatment of esophageal and cardia cancer, which appears to have enhanced the efficiency of PDT. Lasers Surg. Med. 26:308-315, 2000. (C) 2000 Wiley-Liss, Inc.