Photodynamic therapy enhancement of anti-tumor immunity.

Photodynamic therapy (PDT) is an FDA-approved modality for the treatment of early-stage disease and palliation of late-stage disease. Pre-clinical studies using mouse models and clinical studies in patients have demonstrated that PDT is capable of influencing the immune system. The effect of PDT on the generation of anti-tumor immunity is regimen-dependent and is tightly linked to the degree and nature of inflammation induced by PDT. However, the precise mechanism underlying PDT-regulated adaptive anti-tumor immunity remains unclear. This review will focus on the current knowledge of immune regulation by PDT.