Laser-Induced Fluorescence Diagnosis and Photodynamic Therapy of Human Renal Cell Carcinoma

Publisher Website
Google Scholar
Abstract
Photodynamic therapy (PDT) has recently attracted mucht attention, especially among urologists, because it appears to be a selective form of cancer treatment which causes minimal damage to normal surrounding tissues. In this study we made use of a new class of photosensitizers for the laser-induced fluorescence diagnosis (LIFD) and photodynamic therapy of human renal cell carcinoma xenotransplanted into nude mice. The purpose of this study was to evaluate the recently developed photosensitizing drug THOPP-MPEG for its efficacy as photosensitizer for LIFD and PDT of renal cell carcinoma. THOPP-MPEG was injected intraperitoneally (0.5 µg/g body weight) into the mice 6–8 days after tumor transplantation. On the 18th day after transplantation, the tumors reached a diameter of 3–4 mm. Seven days after administration of the drug the tumor-bearing kidney was irradiated percutaneously with a total light dose of 2 × 60 J/cm2 and a power density in the irradiated area of less than 150 mW/cm2. A continuous-beam argon-pumped dye laser (656 nm) was used. After excitation with laser light (488–514 nm), the vital tumor clusters and the surrounding tissues invaded with tumor cells showed intense red coloration by laser-induced fluorescence. Subsequent to the light exposure (656 nm), a heavy tumor necrosis of up to 3–5 mm resulted. No THOPP-MPEG phototoxicity in normal surrounding tissue at a dose of up to 100 mg/ kg body weight was seen. We believe the future role of PDT in the management of tumors of the kidney to be adjuvant within the concept of conservative kidney-preserving surgery.

This publication has 0 references indexed in Scilit: