IFNG and neoplasm: Inflammatory responses induced by reactive oxygen species (ROS) is believed to be the key priming event in the development of anti-tumor immunity.12 The phototoxic reaction following HY-PDT initiates the release of proinflammatory mediators by triggering the release of interleukin (IL)-1α, IL-1β, Interferon (IFN)-γ, IL-6, tumor necrosis factor (TNF)-α and certain other chemokines that provoke a strong inflammatory response in PDT-treated tumor cells.13 Of note, IL-6, a pleiotropic cytokine implicated with barrier functions, is reported to trigger Th17 expansion.