Development and Validation of a Diagnostic Histopathological Scoring System for Capsular Contracture Based on 720 Breast Implant Capsules.

BACKGROUND: Capsular contracture is traditionally evaluated with the Baker classification, but this has notable limitations regarding reproducibility and objectivity. OBJECTIVES: The aim of this study was to develop and validate procedure-specific histopathological scoring systems to assess capsular contracture severity. METHODS: Biopsies of breast implant capsules were used to develop histopathological scoring systems for patients following breast augmentation and breast reconstruction. Ten histological parameters were evaluated by multivariable logistic regression to identify those most associated with capsular contracture. Significant parameters (P < .05) were selected for the scoring systems and assigned weighted scores (1-10). Validation was assessed from the area under the curve (AUC) and the mean absolute error (MAE). RESULTS: A total of 720 biopsies from 542 patients were included. Four parameters were selected for the augmentation scoring system, namely, collagen layer thickness, fiber organization, inflammatory infiltration, and calcification, providing a combined maximum score of 26. The AUC and MAE for the augmentation scoring system were 81% and 0.8%, which is considered strong. Three parameters were selected for the reconstruction scoring system, namely, fiber organization, collagen layer cellularity, and inflammatory infiltration, providing a combined maximum score of 19. The AUC and MAE of the reconstruction scoring system were 72% and 7.1%, which is considered good. CONCLUSIONS: The new histopathological scoring systems provide an objective, reproducible, and accurate assessment of capsular contracture severity. We propose these novel scoring systems as a valuable tool for confirming capsular contracture diagnosis in the clinical setting, for research, and for implant manufacturers and insurance providers in need of a confirmed capsular contracture diagnosis.

Differences of embedding adipose-derived stromal cells in natural and synthetic scaffolds for dermal and subcutaneous delivery.

BACKGROUND: In recent years, adipose-derived stromal cells (ASCs) have been heavily studied for soft tissue regeneration, augmentation, and dermal wound healing. METHODS: In this review, we investigated the trends in injectable scaffolds for ASC delivery in the dermis, and injectable or implantable scaffolds for ASC delivery in the subcutis. A total of 547 articles were screened across three databases; of these, 22 studies were found to be eligible and were included. The scaffolds were subdivided and analyzed based on their tissue placement (dermis or subcutis), delivery method (injected or implanted), and by the origin of the materials (natural, synthetic, and combinatory). RESULTS: ASCs embedded in scaffolds generally showed improved viability. Neovascularization in the transplanted tissue was greater when undifferentiated ASCs were embedded in a combinatory scaffold or if differentiated ASCs were embedded in a natural scaffold. ASCs embedded in natural materials underwent more adipogenic differentiation than ASCs embedded in synthetic scaffolds, indicating an etiologically unknown difference that has yet to be described. Increased mechanical strength of the scaffold material correlated with improved outcome measurements in the investigated studies. Wound healing studies reported reduced healing time in all except one article due to contraction of the control wounds. CONCLUSIONS: In future clinical trials, we recommend embedding ASCs in injectable and implantable scaffolds for enhanced protection, retained viability, and improved therapeutic effects. TRIAL REGISTRATION: This review was registered with PROSPERO: ID=CRD42020171534 . The use of scaffolds as a vehicle for ASC delivery generally improved cell viability, angiogenesis, and wound healing in vivo compared to utilizing ASCs alone. ASCs embedded in natural materials induced more adipogenesis than ASCs embedded in synthetic materials. Adipogenic-induced ASCs further increased this effect. The included studies indicate that the seeded scaffold material influences the differentiation of ASCs in vivo. All studies investigating the mechanical strength of ASC scaffolds reported improved outcome measurements with improved mechanical strength. The results suggest that scaffolds, in general, are favorable for ASC delivery. We recommend initiating clinical studies using scaffolds based on mechanical properties and tunability to improve ASC viability. For fat regeneration, natural scaffolds are recommended.