BACKGROUND: The skin, the largest organ in the human body, is composed of complex layers that include subcutaneous adipose tissue. Understanding the characteristics of this skin structure is essential to optimize therapeutic interventions, such as cryolipolysis, aiming for more effective and personalized results. OBJECTIVE: To evaluate the immunohistochemical effects of skin tissue in adult women undergoing cryolipolysis. MATERIALS AND METHODS: We carried out an experimental and blind study with immunohistochemical analysis in women with localized abdominal fat, categorized based on the constitution of the skin as flaccid or firm according to the Investigator Assessment Skin Laxity Scoring System scale. Participants were randomized before undergoing the cryolipolysis procedure. Forty-five days after the procedure, they underwent abdominoplasty, with collection of biological material. We evaluated the inflammatory markers EBF-1, TNF-alpha, and CD68, as well as Caspase 3, cleaved Caspase 3, apoptotic BCL2, Ki-67 for fibroblast proliferation, and FIS1 for mitochondrial proliferation. RESULTS: Six women were included, divided into two groups
three women with loose and three with firm skin. We observed that after cryolipolysis, the group with flaccid skin showed higher expression of the Casp3, TNF-alpha, BCL2, and FIS1 markers compared to those with firm skin. CONCLUSION: Cryolipolysis may act differently according to tissue morphology, suggesting that its apoptotic response is more pronounced in the group with flaccid skin. https://doi.org/10.54680/fr25110110212.