Photodynamic Therapy and Applications in Cancer

 The idea of using light as a therapeutic tool has been popular for thousands of years. Scientific discoveries in line with technological innovations have contributed to the advancement of photodynamic therapy as a therapeutic modality. Photodynamic therapy is based on the generation of highly reactive species that alter the molecular systematics of cells through interactions between light, photosensitizer, and molecular oxygen. It has a minimally invasive protocol that can be combined with other clinical methods or can be stand-alone. The development of photosensitizers with the integration of nanotechnological approaches has provided favorable results over the years in malignant and non-malignant diseases by facilitating target-site action, selectivity, and controllable drug release. This chapter presents a review of photodynamic therapy with its important aspects; history, mechanism of action, cellular effects, integration into nanoscale drug delivery systems, and combinational therapeutic approaches in cancer. 

Keywords: Anticancer therapy, Apoptosis, Autophagy, Cancer, Tumor, Cell death, Clinical application, Combination therapy, Drug delivery systems, Immunogenic cell death, Light therapy, Nanotechnology, Necroptosis, Necrosis, Neoplasms, Photodynamic therapy, Photosensitizer, Reactive oxygen species, Singlet oxygen, Vascular endothelium.