During radiation therapy, the skin at the irradiated site (the unirradiated site will not have any skin reaction) will have the same reaction as after excessive sun exposure, with redness, itching, flaking, and hair loss at the hairy site (but most of the hair can grow back after the radiation therapy is finished). A small number of patients with severe reactions or inappropriate skin care may develop local skin erosion (in most cases, the skin can return to normal after suspending radiation therapy for 1~2 weeks, which has little effect on the completion of the radiation therapy plan and the efficacy of the treatment). Therefore, during radiation therapy, we must pay attention to: 1. protect the dry and clean skin of the irradiated area, just wash the skin of the irradiated area with warm water when bathing, avoid scrubbing the irradiated skin with various shower gels or soaps, and also pay attention to never washing off the marking points and lines of various positioning and irradiation fields. In order to avoid inaccurate positioning during radiotherapy due to unclear marking lines. The skin of the irradiated area must avoid contact with perfumes or skin care products; 3.