RECENT ADVANCES IN PHOTODYNAMIC THERAPY

Photodynamic therapy is a relatively new clinical modality consisting of systemic administration of a photosensitizing dye that is preferentially retained by tumors. Photodamage occurs when the sensitized tissue is irradiated with light at a wavelength corresponding to the absorption bands of the photosensitizer. The result is a highly selective form of tumor eradication. A review of the literature indicates that a variety of veterinary tumors can be effectively treated with photodynamic therapy. Minimum toxicity has been noted, This technique does not seem to share cross-resistance with other treatment modalities and can be repeatedly administered without additive toxic effects. Its potential for diagnostic imaging is also promising.