Photodynamic therapy enhanced by hyperbaric oxygen in acute endoluminal palliation of malignant bronchial stenosis (clinical pilot study in 40 patients).

OBJECTIVES Photodynamic tumor therapy (PDT) is based upon a photochemical reaction that is limited by the availability of molecular oxygen in the target tissue. The use of hyperbaric oxygenation (HBO) increases the amount of oxygen available for the process may thereby enhance the efficacy of PDT. We proved in a prospective, non-randomized clinical pilot study the acute effects on malignant bronchial stenosis and the technical feasibility of combined PDT/HBO. METHODS Forty patients (29 males, 11 females, mean age: 64.3 years; range 39-82 years) with inoperable, advanced malignant bronchial tumor stenosis were studied prospectively. Photosensitization was carried out using a hematoporphyrin-derivative 2 mg/kg bw 48 h prior to PDT. The light dose was calculated as 300 J/cm fiber tip. The assessment of outcome 1 and 4 weeks after PDT/HBO was done by endoscopy, chest X-ray, spirometry, laboratory parameters, subjective report of dyspnea and Karnofsky performance status. RESULTS At 1 and 4 weeks after the treatment the patients felt a significant improvement of dyspnea and hemoptysis alongside with an objective subsiding of poststenotic pneumonia, though spirometric parameters revealed no significant difference. A significant reduction of tumor stenosis (P<0.05) and an improvement of the Karnofsky performance status (P<0.05) were documented 1 and 4 weeks after PDT/HBO. No therapy related complications were observed. CONCLUSION Although the small number of patients does not allow to draw definitive conclusions, the results suggest that combined PDT/HBO represents a new, safe and technically feasible approach. It enables efficient and rapid reduction of the endoluminal tumor load and helps conditioning the patient for further treatment procedures.