In a German single-institution study reported in JAMA Oncology, Hülpüsch et al identified skin microbiome characteristics associated with severe radiodermatitis in women receiving adjuvant radiotherapy for breast cancer.
Study Details
The study included 20 consecutively enrolled women who received 7 weeks of adjuvant radiotherapy following surgery between January 2017 and January 2019 at an urban academic university cancer center (Technical University Munich). Patients had a median age of 61 years (range = 37–81 years) Preradiation skin microbiome samples were analyzed using 16S (V1-V3) amplicon sequencing; quantitative polymerase chain reaction (PCR) was performed for skin bacterial enumeration after initiation of radiotherapy.
Key Points
Radiation-associated skin symptoms were mild in seven patients, moderate in nine, and severe in four. A total of 360 samples were analyzed, taken before, during, and after radiotherapy, from both the treated and contralateral healthy sides.
The 16S sequencing showed that low (< 5%) relative abundance of commensal skin bacteria (ie, Staphylococcus epidermidis, Staphylococcus hominis, Cutibacterium acnes) prior to radiotherapy was associated with the development of severe radiodermatitis, with an accuracy of 100% (100% sensitivity and specificity, P < .001).
Among patients with severe radiodermatitis, qualitative PCR bacterial enumeration showed general non–species-specific overgrowth of skin bacterial load prior to onset of severe symptoms. During severe radiodermatitis, the abundance of commensal bacteria increased, while total bacterial load decreased.
The investigators concluded, “The findings of this observational study indicated a potential mechanism associated with the skin microbiome for the pathogenesis of severe radiodermatitis, which may be a useful biomarker for personalized prevention of radiodermatitis in patients undergoing adjuvant radiotherapy for breast cancer.”
Claudia Traidl-Hoffmann, MD, of the Department of Environmental Medicine, University of Augsburg, is the corresponding author for the JAMA Oncology article.
Disclosure: For full disclosures of the study authors, visit jamanetwork.com.
