Topical Diclofenac for Prevention of Radiation-induced Dermatitis

Inclusion Criteria: 1. Male and female which are 18 years of age or older 2. Performance status \< 2 3. Epithelial carcinoma of oropharynx, nasopharynx, larynx, hypopharynx, paranasal sinus and salivary glands or breast cancer, planned to receive a total dose of at least 50 Gy 4. The RTOG radiation dermatitis rating should be equal to 0 and the skin nutrition should be good 5. The main organs are functioning normally and meet the following standards: (1) Blood routine examination must meet the following criteria: (no blood transfusion within 14 days) a. HB ≥ 100g/L, b. WBC ≥3×10\^9/L c. ANC≥1.5×10\^9/L, d. PLT ≥100×10\^9/L; (2) Biochemical examination must meet the following standards: a. BIL\<1.5 times the upper limit of normal value (ULN), b. ALT and AST\<2.5ULN, GPT ≤1.5×ULN; c. Serum Cr≤1 ULN, endogenous creatinine clearance rate\>60ml/min (Cockcroft Gault formula);(3).Good coagulation function: defined as International standardized ratio (INR) or prothrombin time (PT) ≤1.5×ULN;(4).The myocardial enzyme spectra were in the normal range. 6. Patients willing and able to give signed informed consent and, in the opinion of the Investigator, to comply with the Clinical Investigation Plan tests and procedures. Exclusion Criteria: 1. Pregnant or lactating women 2. A known history of intolerance or allergy to any component of the investigational product; 3. severe cardiopulmonary disease (such as unstable angina attacks, grade II cardiac insufficiency, acute myocardial infarction, acute episodes of chronic obstructive pulmonary disease, pulmonary heart disease); 4. The acute phase is accompanied by inflammatory skin diseases, such as atopic dermatitis, contact dermatitis, psoriasis, lichen planus, pityriasis rosea. 5. Systemic diseases known to delay the skin healing process, such as diabetes or severe kidney failure; 6. Skin rupture caused by malignant tumors.