The Association Between Radiation Dermatitis and Skin Microbiome in Breast Cancer Patients

Radiotherapy is an important treatment for breast cancer patients. About 95% of patients receiving radiotherapy will develop a degree of radiation dermatitis. Radiation dermatitis is usually limited to the site of radiation treatment. Symptoms vary and can range from itching, burning and pain to open or bleeding ulcers, which can greatly affect the quality of life of patients. Severe acute radiation dermatitis can lead to interruption or delay of treatment. At present, there is no standard for the prevention and treatment of radiation dermatitis. Our skin is home to millions of bacteria, fungi and viruses which compose the skin microbiota. Skin microbiota interacts with skin and affects physiology and immunity of the skin. Previous studies have reported the effects of radiotherapy on skin and immune system. However, so far, no studies have analyzed the effects of radiotherapy on skin microbiome and how skin microbiome affects the skin immune responses after radiotherapy. In this study, the breast cancer patients who received radiotherapy after mastectomy and breast reconstruction will be enrolled. The skin microbiome before radiotherapy and its changes after radiotherapy will be analyzed systematically to find out whether the skin microbiome is associated with the severity of radiation dermatitis. The long-term goal of this study is to deepen the understanding of the role of skin microbiome in the occurrence and development of radiation dermatitis, and provide a basis for subsequent exploration to reduce radiation dermatitis by regulating skin microecology.

Inclusion criteria

• Female patients
• Invasive breast cancer confirmed by pathology
• Underwent mastectomy and breast reconstruction
• Radiotherapy after breast reconstruction
• ECOG score 0-1
• Signed informed consent

Exclusion criteria

• Previous breast or chest radiotherapy
• Other serious skin diseases (systemic lupus erythematosus, skin sclerosis, et al) and cannot receive radiotherapy
• Pregnant women
• Patients who are unwilling or unable to receive regular follow-up.