The photodynamic therapy: state of the art and perspectives

Abstract

International audiencePhotodynamic therapy (PDT) is a method of medical treatment using the concomitant action of aphotoactivatable molecule called the photosensitizer (PS), light, and oxygen naturally present in thebiological medium. After light excitation of the photosensitizer, an energy transfer to oxygen allows togenerate the formation of reactive oxygen species, especially singlet oxygen reactive leading to cell death.This technique proves to be very efficient for certain types of cancer (especially in dermatology) and ispromising in other pathologies (prostate, brain). This article briefly describes the principle of PDT and thenanalyzes the latest advances in PDT in terms of clinical applications (actinic keratoses, prostate, braincancer, retinoblastoma) and the use of PDT for antibacterial applications. Finally, the prospects of thistechnique with among others the development of new vesicles or the use of X-rays as a source of energy toovercome the problems of light penetration in tissues are presented