Photodynamic diagnosis in respiratory tract malignancy using an excimer dye laser system

Equipment has been developed for the early-stage diagnosis and treatment of cancer using an excimer dye laser. The excimer laser beam is obtained by exciting XeCl. A 405 nm beam tuned by DPS dye is used for tumour localization and a 630 nm beam obtained with a rhodamine B dye is used for treatment. The equipment was applied clinically on the basis of extensive experimental research. Effectiveness for cancer localization was examined in 11 cases: four were early stage (three lung cancer and one vocal cord cancer), four were stage I, two were stage III and one was stage IV. All cases were squamous cell carcinoma except for one case of adenocarcinoma. Fluorescence was recognized in all lesions and the equipment was effective for localization.