Fenofibrate is a specific ligand for PPARα, which has been used for the treatment of hypercholesterolemia, hypertriglyceridemia, diabetes and cardiovascular diseases for long time. Fenofibrate reduces low-density lipoprotein (LDL), very low density lipoprotein (VLDL) and triglyceride levels, while increases high-density lipoprotein (HDL) levels. PPARα has also shown antioxidant and anti-inflammatory properties. Fenofibrate confers cytoprotective effect against myocardial ischemia-reperfusion (I/R) injury in rats by suppressing cell apoptosis and ameliorates age-related renal injury through the activation of AMPK and SIRT1 signaling. However, the safety and effectiveness of fenofibrate on the progression of radiation-induced skin injury remain unknown. The purpose of this study is to determine whether topical application of fenofibrate is safe and effective for radiation-induced skin injury.

Radiation-induced skin injury is a significant side effect of ionizing radiation delivered to the skin during cancer treatment as well as a result of other exposure to radiation. The skin is one of radiosensitive organ systems in human body because it is a continuously renewing organ containing rapidly proliferating and maturing cells. Ionizing radiation promotes reactive nitrogen and oxygen species (RNS/ROS) production due to radiolysis of water and direct ionization of target molecules, which result in oxidative damage and skin injuries. It is considered that ~95 % of cancer patients receiving radiation therapy will develop some form of radiodermatitis, including erythema, dry desquamation, and moist desquamation. Radiation-induced skin injury negatively affects the process of radiotherapy and the quality of patients' life. Despite substantial improvements in radiation technology, radiation-induced skin toxicity is still a concerning problem. The purpose of this study is to determine whether topical application of fenofibrate is safe and effective for radiation-induced skin injury.

Inclusion Criteria:

• Eligible patients had to have a pathologically proven cancer with a planned course of radiotherapy.
• Normal haematological function (granulocyte count > 1.5 X 109 cells per litre, platelet count > 100 X 109 cells per litre and haemoglobin > 100 g/L) and organ function (creatinine clearance > 50 mL/min) and aspartate aminotransferase/alanine aminotransferase < 2.5 of upper normal limit).

Exclusion Criteria:

• The presence of rash or unhealed wound in the radiation field, known allergy or hypersensitivity to fenofibrate, pregnancy or lactation, history of/current connective tissue disorder and prior radiation to the thorax.