Influence of drug and light regimens in determining PDT efficacy with lutetium texaphyrin

摘要

Lutetium texaphyrin (PCI-0123) is a pure, stabile, water-soluble photosensitizer with a broad absorption band centered at 732 nm. Lutetium texaphyrin has shown considerable promise in the treatment of murine mammary tumors. PDT requires the coexistence of a photosensitizer, oxygen and light. Light fluences, rates and delivery methods have a profound influence on oxygen depletion and re-equilibration and therefore tumor responsiveness. The effect of different photoirradiation and sensitizer dose in eradicating/retarding EMT6 tumors in BALB/c mice using lutetium texaphyrin was evaluated. An increase in light fluences increased efficacy. No difference was observed between a continuous versus a fractionated light protocol. A reduction in time between sensitizer injection and laser treatment enhanced tumor treatment.