Management of Oral Premalignant Lesions Using Topical Photodynamic Therapy: An Overview
Dr. Mahendra RR Patait, Dr. Shakthi Natrajan, Dr. Shekhar Rajderkar, Avinash Khairnar
Photodynamic Therapy (PDT), a widely investigated therapeutic tool in the local management of premalignant lesions, is based on the topical administration of a photosensitive drug which preferentially accumulates in tumor tissues. This target site when irradiated with an appropriate wavelength of light triggers a photochemical reaction resulting in the production of singlet oxygen having cytotoxic effects. Agents used in the past include haematoporphyrins, photofrin, dyes and non-thermal lasers. Before formulating PDT as the first line of treatment, protocols such as illumination scheme, light source, lesion size, thickness of surface keratin and degree of epithelial dysplasia must essentially be considered. This paper provides an overview on the newer Topical Aminolevulinic acid (ALA) based PDT, which, owing to its high efficacy, low side effects, high patient compliance, low toxicity and minimal tissue invasion is believed to have potential to play a significant role in the management of low-grade dysplasia.