PHOTODYNAMIC THERAPY FOR THE TREATMENT OF SQUAMOUS-CELL CARCINOMA USING BENZOPORPHYRIN DERIVATIVE

BACKGROUND. Photodynamic therapy (PDT) involves laser light excitation of a tumor-localizing photosensitizer to destroy neoplasms. Benzoporp hyrin derivative (BPD) is a new photosensitizer with several favorable characteristics. OBJECTIVE. Studies were designed to: 1) assess the e fficacy of BPD-mediated PDT in treating in vivo squamous cell carcinom as (SCC); 2) obtain dosimetry data for BPD and laser parameters; and 3 ) establish clinical and histologic correlates of BPD-induced tumor re gression. METHODS. Human SCC was implanted into nude mice. One group r eceived BPD followed by laser light of 150 J/cm2 from an argon-pumped dye laser at 690 nm. Three control groups included laser energy alone, BPD alone, and no treatment. RESULTS. At day 21 posttreatment only PD T-treated tumors showed a statistically significant decrease in tumor volume and complete cure rate. Clinical resolution (scar) correlated p erfectly with histologic resolution (scar). CONCLUSION. Human SCC in a nude mouse model responds to BPD-mediated PDT.