Skin Microbiome

The purpose of this study is to build insights to understand how the placebo and active impacts the skin microbiome in women with high skin sensitivity (SS10 \> 13) and sun exposure. Microbiome samples will be taken at baseline after 2 weeks of using the placebo (base without active) as a run-in period followed by the usage of placebo for an additional 4 weeks. The participants will then start the usage of active formula for an additional 8 weeks with microbiome samples collected at the 10-week and 14-week. This will allow us to observe how the microbiome changes over time after the product usage of both placebo and active formulations relative to the pre-regimen condition. In addition, headshot photos will be taken using the Haut AI application at each time point concurrent to the microbiome sample collection to examine changes in skin appearances after the regimen.

Acute radiation dermatitis (ARD) is the most common treatment-related adverse reaction following radiotherapy after modified radical mastectomy and/or prosthetic breast reconstruction in breast cancer patients. Moderate-to-severe ARD may compromise cosmetic outcomes and quality of life, and even impair radiotherapy efficacy. Current pharmacological prophylactic measures clinically employed - including topical corticosteroids, superoxide dismutase, and trolamine cream - demonstrate suboptimal efficacy and lack high-level evidence-based medical support. Emerging research indicates an association between cutaneous microbial homeostasis and ARD development, suggesting that maintaining skin surface acidity and modulating microecological balance may represent more effective preventive strategies. This study evaluates the efficacy and safety of a natural weak-acid macromolecular/small molecular repair cream in preventing ARD among post-operative breast cancer patients receiving radiotherapy through skin microbiome modulation. We enrolled 326 high-risk early-stage breast cancer patients scheduled for post-operative radiotherapy and randomized them to compare the superiority of the natural weak-acid repair cream versus conventional care with moisturizer. Concurrent skin microbiome sampling was performed to assess microecological changes and their impact on ARD development. The findings will provide high-level clinical evidence and theoretical basis for the safer and more effective application of this natural weak-acid repair cream in preventing post-radiotherapy ARD in breast cancer patients.

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.