Top Line: How does the skin microbiome influence the risk of dermatitis from breast radiation?
The Study: Last year, we saw a study that found Staph aureus colonization is more common among patients who develop radiation dermatitis compared to those who don’t. A follow-on randomized trial then found that Staph aureus decolonization lowered the rate of dermatitis. Here’s another prospective longitudinal study that monitored the skin microbiome of 20 patients receiving breast radiation. Samples of the skin microbiome from the irradiated breast and contralateral breast were taken prior to treatment, weekly during treatment, and after treatment. A baseline low (<5%) abundance of the commensals Staph epidermidis, Staph hominis, and Cutibacterium acnes was significantly associated with the risk of severe dermatitis. In fact, 100% of patients with low baseline commensal abundance had severe dermatitis. It was also observed that patients who developed severe dermatitis had a large increase in bacterial load during treatment. Importantly, this increase was observed early in treatment on the affected side and before the onset of toxicity.
TBL: This small longitudinal study found that patients who develop severe dermatitis from breast radiation had a low abundance of commensal bacteria at baseline and experienced a significant increase in skin bacterial load prior to the onset of toxicity. | Hulpusch, JAMA Oncol 2024
The Study: Last year, we saw a study that found Staph aureus colonization is more common among patients who develop radiation dermatitis compared to those who don’t. A follow-on randomized trial then found that Staph aureus decolonization lowered the rate of dermatitis. Here’s another prospective longitudinal study that monitored the skin microbiome of 20 patients receiving breast radiation. Samples of the skin microbiome from the irradiated breast and contralateral breast were taken prior to treatment, weekly during treatment, and after treatment. A baseline low (<5%) abundance of the commensals Staph epidermidis, Staph hominis, and Cutibacterium acnes was significantly associated with the risk of severe dermatitis. In fact, 100% of patients with low baseline commensal abundance had severe dermatitis. It was also observed that patients who developed severe dermatitis had a large increase in bacterial load during treatment. Importantly, this increase was observed early in treatment on the affected side and before the onset of toxicity.
TBL: This small longitudinal study found that patients who develop severe dermatitis from breast radiation had a low abundance of commensal bacteria at baseline and experienced a significant increase in skin bacterial load prior to the onset of toxicity. | Hulpusch, JAMA Oncol 2024