[Laser photodynamic therapy for central-type lung cancer]

Laser endoscopic surgery is recognized as an effective treatment for lung cancer. Attention has increasingly been focused on photodynamic therapy (PDT) with dihermatoporphyrin ethers. The Japanese government approved the use of this therapy in October 1995, and reimbursement through the national health insurance system began in April 1996. Over the past decade, 140 patients (283 lesions) with central type lung cancers have been treated at our hospital. Overall complete remission was obtained in 39.6% of 112 lesions, partial remission in 59.4% and no remission in 1.0% The indications for PDT are as follows: 1. Early stage lung cancer curative; among 95 early stage lesions complete remission was obtained in 79 (83.2%), and 71 patients were disease free at 3 to 176 months. 2. Advanced lesions opening of bronchi; overall, "effective" opening of bronchi was achieved in 61 of 81 lesions (75%), in the PDT group, and in 143 of 177 (81%) in the Nd-YAG laser therapy groups. 3. Preoperative laser irradiation to increase operability and reduce the extent of operation; the extent of resectin was reduced, or inoperable lesions were made operable in 21 of 24 patients treated. 4. Multiple primary lung cancer. The success of clinical trials of PDT for treatment of lung cancers bodes well for its future use. More stable, definitive, and successful treatment will become possible with the use of new dyes that distribute more evenly in tumor tissue, and with the deeper tissue penetration made possible by longer-wavelength beams.