EGF and cancer: Radiotherapy enhances the levels of cytokines, which are responsible for inflammation, proliferation, and disease progression in HNC, especially in oral squamous carcinoma patients [5]. Cytokines regulate cell proliferation, enhance the formation of new blood vessels, help cancer cells to invade adjust tissues, and promote cell survival [6]. The most frequently analyzed cytokines in saliva are interleukin-6 (IL-6), interleukin-8 (IL-8), and epidermal growth factor (EGF) [7]. These specific proteins are widely used as prognostic biomarkers.