2007 Volume 18 Issue 1 Pages 9-15
Photodynamic therapy (PDT) enables selective treatment of tumor tissue, by combining the use of a photosensitizer, which is specifically taken up by tumor tissue and newly formed blood vessels, and induces cytocidal effects by highly active oxygen created by laser excitation, without damaging surrounding normal tissue.
PDT holds hope for elderly patients and patients at high risk, because PDT preserves organ function and is less invasive than surgery.
The first generation of tumor photosensitizers was a porfimer sodium (Photofrin®), and the second generation includes talaporfin sodium (Laserphyrin®) and verteporfin (Visudyne®). These procedures are all recognized and reimbursed by the health insurance system of Japan.
We performed preclinical experiments on PDT and photodynamic diagnosis (PDD) using Laserphyrin. Microscopically, scat tered fluorescence from Laserphyrin in tumor tissue was observed in a fresh malignant tumor specimen obtained 2 hours af ter injection, and the treatment effect of PDT using Laserphyrin was recognized in mouse tumors which had received trans planted human squamous cell carcinoma cells.
We subsequently applied Laserphyrin in clinical cases and report the results in a case of tongue cancer. Good results were obtained with both PDD and PDT.
