Porphyrins for Imaging, Photodynamic Therapy, and Photothermal Therapy

The interest in the use of light to detect and treat cancer has grown exponentially concurrent with advances in light technology, understanding of the optical properties of tissues, and the development of optical probes. The medical applications of photonics encompass both diagnostic and therapeutic interventions. As with many oncologic treatment strategies, the clinical utilization of light suffers from some practical constraints. However, these may be circumvented by the use of exogenous contrast agents. In the past century, porphyrins-multimodal, naturally-occurring molecules-have been widely studied, both in nature and in biomedical applications. This chapter discusses the application of light in medicine and the role of porphyrins in photonic diagnostics and interventions as well as applications beyond photonics and strategies for improving on their utilization in oncology.