LAUSR

Background: Although implant-based breast reconstruction is a common surgical modality, a periprosthetic capsule inevitably forms and worsens in cases of postmastectomy radiation therapy. Previous animal studies have reported that antiadhesive agents (AAAs) inhibit periprosthetic capsule formation. The authors prospectively examined the clinical effects of an AAA (Mediclore) on capsule formation in implant-based breast reconstruction. Methods: The authors analyzed patients who underwent immediate two-stage implant-based breast reconstruction following total mastectomy for breast malignancy between November of 2018 and March of 2019. Each patient was randomly allocated to the control or AAA group. After inserting the breast expander and acellular dermal matrix, AAA was applied around the expander before skin closure. The capsule specimen was obtained during the expander-implant change; capsule thickness and immunohistochemistry were investigated. Results: A total of 48 patients were enrolled and allocated to the control (n = 22) and AAA (n = 26) groups. There were no significant differences in patient- and operation-related characteristics. Submuscular capsule thickness was significantly reduced in the AAA group compared with the control group. The levels of pro–capsular-forming cells (myofibroblasts, fibroblasts, and M1 macrophages) in the capsule were significantly lower in the AAA group than in the control group. Conclusions: AAA reduced the thickness of periprosthetic capsules and changed the profiles of cells involved in capsule formation during the tissue expansion. These findings demonstrate the clinical value of AAA for mitigating capsule formation in implant-based breast reconstruction. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.