IL17A and neoplasm: Epidermal keratinocytes are responsive to dendritic cell-derived and T-cell-derived cytokines such as IFNs, TNF, IL-6, IL-17 and the IL-20 family of cytokines and vice versa, they are able to release proinflammatory cytokines and chemokines to sustain or even amplify the chronic inflammatory disease loop in lesional skin in psoriasis1.