The critical role of IL-17A in the initiation and maintenance of tissue inflammation is well known.30 Published data have documented a significant increase in the populations of Th17 or IL-17A-positive cells and expression levels of IL-17A in various irradiated tissues.39,40,43 Mieczkowska et al.40 demonstrated a positive correlation between the increased IL-17A level and the severity of tissue injury in irradiated skin, providing evidence for the contribution of IL-17A to the disease progression of radiation-induced dermatitis (RID) in mice. Here, IL17A is linked to radiodermatitis.