Skin Microbiome, Inflammation, and Skin Toxicities in Women With Breast Cancer Receiving Moderately Hypofractionated Radiation Therapy.

purposeUp to 95% of women during and after radiation therapy (RT) for breast cancer have reported cutaneous toxicity. However, the biologic link between skin microbiome and skin toxicities from RT remains largely unknown. This study aimed to assess the associations of skin microbiome with clinician- and patient-reported skin toxicities and inflammatory markers in women with breast cancer receiving RT. METHODS AND MATERIALS: A prospective, longitudinal study was conducted at a single institution. Thirty-two women with breast cancer undergoing moderately hypofractionated RT for 3 to 4 weeks after breast conserving surgery were enrolled and 30 of them were analyzed. A total of 240 swabs for skin microbiome and 120 plasma samples were collected pre-RT baseline (T

resultsDifferences in skin microbiome of the treated breasts during RT (T

conclusionsThis study shows changes in the skin microbiome during well-tolerated moderately hypofractionated breast RT. The skin microbiome return toward baseline appears to associate with improvement of clinician- and patient-reported skin toxicities post-treatment. Although there were few high-grade toxicities observed among frequently prescribed courses of hypofractionated whole breast RT, changes in skin microbiome may be of interest as further targets of symptomatic relief or intervention as ultrahypofractionated courses become more common.