Beneficial effects of transdermal administration of tamoxifen on capsular contracture after breast implantation in murine models

Incidence and Risk Assessment of Capsular Contracture in Breast Cancer Patients following Post-Mastectomy Radiotherapy and Implant-Based Reconstruction

Our study aims to identify the risk factors and dosimetry characteristics associated with capsular contracture.

METHODS

We retrospectively analyzed 118 women with breast cancer who underwent PMRT following an IBR between 2010 and 2022. Patients were treated with PMRT of 50.0-50.4 Gy in 25-28 fractions. Capsular contracture was categorized according to the Baker Classification for Reconstructed Breasts.

RESULTS

After a median follow-up of 22 months, the incidence of clinically relevant capsular contracture (Baker III-IV) was 22.9%. Overall, capsular contracture (Baker I-IV) occurred in 56 patients (47.5%) after a median of 9 months after PMRT. The rate of reconstruction failure/implant loss was 25.4%. In the univariate analysis, postoperative complications (prolonged pain, prolonged wound healing, seroma and swelling) and regional nodal involvement were associated with higher rates of capsular contracture (p = 0.017, OR: 2.5, 95% CI: 1.2-5.3 and p = 0.031, respectively). None of the analyzed dosimetric factors or the implant position were associated with a higher risk for capsular contracture.

CONCLUSION

Postoperative complications and regional nodal involvement were associated with an increased risk of capsular contracture following breast reconstruction and PMRT, while none of the analyzed dosimetric factors were linked to a higher incidence. Additional studies are needed to identify further potential risk factors.

The activation of FPR3/PKA/Rap1/ERK1/2 and FPR3/p-IκB/NF-κB axis in fibroblasts promote capsular contracture after rhinoplasty

BACKGROUND

Capsular contracture may occur after rhinoplasty due to rejection of silicone implants by the immune system. Our previous high-throughput sequencing of RNA in nasal capsular contracture tissue revealed that FPR3 was significantly increased in grade IV capsular contracture tissue, compared with grade II.

OBJECTIVE

This study aimed to elucidate the effect and specific mechanism of FPR3 on capsular formation and contracture following rhinoplasty.

METHODS

Using the GeneMANIA Database, the genes involved with FPR3 expression were searched, and the Gene Ontology analysis was performed to annotate the biological functions of the aforementioned genes. The mRNA and protein expressions of related genes in fibroblasts and capsular contracture tissues were analyzed using quantitative real-time PCR, western blot, and immunohistochemical staining. CCK-8 was used to determine the viability of cells. The migration capacity of fibroblasts was assessed using a wound healing assay. ELISA was used to detect levels of IL-1β, TNF-α, and IL-6.

RESULTS

After rhinoplasty, the expression of FPR3 in the capsular tissue increased in proportion to the degree of contracture. By activating the PKA/Rap1/ERK1/2 axis, overexpression of FPR3 can significantly increase the cell viability of fibroblasts and promote their transformation into myofibroblasts. Moreover, FPR3 phosphorylates IκB to decrease NF-κB inhibition, thereby promoting the synthesis and release of the inflammatory cytokines IL-1β, TNF-α, and IL-6.

CONCLUSION

FPR3 is a crucial molecule that causes capsular development and contracture following rhinoplasty. In the future, local suppression of FPR3 may be an effective treatment for relieving capsular contracture.