Oncological Photodynamic Therapy: Considerations on Cell Death and Proliferation is a book that addresses aspects of photodynamic therapy, a technique that adds light to a photosensitive substance and oxygen and has as its therapeutic principle the generation of high levels of oxidative stress, being able to invalidate cells and microorganisms through death cascades that are still poorly understood, has been used in oncology for tumor reduction. The purpose of this study was to establish the anatomical-chronological relationship of cell death markers (caspase 3, beclin 1 and RIP 1 ) and DNA repair protein during the cell cycle (PCNA) present after PDT, in order to verify cell death/proliferation kinetics and suggest the most appropriate time interval between PDT sessions for repeating the therapy, as well as reviewing some families of photosensitizing substances. Cell death mechanisms such as apoptosis, atophagy and necrosis are covered in self-explanatory diagrams and the highlight is the application to chemically-induced potentially malignant oral lesions.