Suppressive Effect of Leukotriene Antagonists on Capsular Contracture in Patients Who Underwent Breast Surgery with Prosthesis: A Meta-Analysis

Montelukast Attenuates Retraction of Expanded Flap by Inhibiting Capsule Formation around Silicone Expander through TGF-β1 Signaling

BACKGROUND

Tissue expansion has tremendous applications in plastic surgery, but flap retraction provides insufficient tissue for use. Inspired by the use of montelukast to suppress capsular contracture, the authors investigated the effects of montelukast on capsule formation around the expander and retraction of the expanded scalp of the rat.

METHODS

Thirty-six male Sprague-Dawley rats were randomly divided into control and montelukast groups. In each group, 12 expanded flaps with or without capsules were harvested for histologic and molecular analysis; the six remaining expanded flaps were transferred to repair defects. Myofibroblast and transforming growth factor-β1 expression in the capsule was determined using immunofluorescence. Capsule ultrastructure was observed using transmission electron microscopy. Related protein expression in the capsules was detected using Western blot analysis.

RESULTS

A comparison of control and montelukast groups revealed that areas of the harvested expanded flaps with capsules were greater (2.04 ± 0.11 cm 2 versus 2.42 ± 0.12 cm 2 , respectively; P = 0.04); the retraction rate decreased (41.3% ± 2.16% versus 28.13% ± 2.17%, respectively; P < 0.01). However, the increased areas and decreased retraction disappeared after capsule removal. The number of myofibroblasts declined. Thin, sparse collagen fibers were observed in the capsules. The expression of COL1, COL3, TGF-β1, EGR1, and phosphorylated ERK1/2 in the capsules decreased. Furthermore, the recipient area repaired by the transferred expanded flap was increased from 4.25 ± 0.39 cm 2 to 6.58 ± 0.31 cm 2 ( P < 0.01).

CONCLUSION

Montelukast attenuates retraction of the expanded flap by inhibiting capsule formation through suppressing transforming growth factor-β1 signaling.

CLINICAL RELEVANCE STATEMENT

This study provides novel insights into a method for increasing the area of the expanded flap.

Identification of Drug Compounds for Capsular Contracture Based on Text Mining and Deep Learning

BACKGROUND

Capsular contracture is a common and unpredictable complication after breast implant placement. Currently, the pathogenesis of capsular contracture is unclear, and the effectiveness of nonsurgical treatment is still doubtful. The authors' study aimed to investigate new drug therapies for capsular contracture by using computational methods.

METHODS

Genes related to capsular contracture were identified by text mining and GeneCodis. Then, the candidate key genes were selected through protein-protein interaction analysis in Search Tool for the Retrieval of Interacting Genes/Proteins and Cytoscape. Drugs targeting the candidate genes with relation to capsular contracture were screened out in Pharmaprojects. Based on the drug-target interaction analysis by DeepPurpose, candidate drugs with highest predicted binding affinity were obtained eventually.

RESULTS

The authors' study identified 55 genes related to capsular contracture. Gene set enrichment analysis and protein-protein interaction analysis generated eight candidate genes. One hundred drugs targeting the candidate genes were selected. The seven candidate drugs with the highest predicted binding affinity were determined by DeepPurpose, including tumor necrosis factor alpha antagonist, estrogen receptor agonist, insulin-like growth factor 1 receptor, tyrosine kinase inhibitor, and matrix metallopeptidase 1 inhibitor.

CONCLUSION

Text mining and DeepPurpose can be used as a promising tool for drug discovery in exploring nonsurgical treatment to capsular contracture.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, V.

Endoscopy-assisted versus open tissue expander placement in plastic and reconstructive surgery: a meta-analysis

Tissue expansion can be used to overcome challenges due to tissue deficiency in plastic and reconstructive surgery; however, the long expansion process is often accompanied by numerous complications. This meta-analysis aimed to determine whether endoscopy-assisted expander placement could decrease complications and shorten treatment time. This study followed the principles of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and was registered in PROSPERO (CRD42021226116). A literature search was performed in eight databases from their inception dates up to 25 August 2021, to identify clinical studies on endoscopy-assisted and/or open tissue expander placement in plastic and reconstructive surgery. Seven studies met the inclusion criteria. In seven studies, 194 underwent endoscopy-assisted expander placement, and 565 underwent open expander placement. The overall complication rate in the endoscopy-assisted group was significantly lower than that in the open group (risk difference (RD) -0.28, 95% confidence interval (CI), -0.38, -0.18, p < .001). Subgroup analysis showed significantly lower incidence rates of hematoma, infection and dehiscence in the endoscopy-assisted group. The complication rate in the head/neck was lower with low heterogeneity (RD, -0.18; 95% CI, -0.26 to -0.09, p < .001; I² = 0%). The endoscopy-assisted group had shorter surgery time, hospital stay and time to full expansion (weighted mean difference (WMD), -13.97 min, -16.88 h, -27.54 days; 95% CI, -15.85, -12.08 min, -24.36, -9.40 h, -38.85, -16.24 days; both p < .001, respectively). Endoscopy-assisted expander placement may help lower the risk of complications, especially in the head/neck, and reduce surgery time, hospital stay, and time to full expansion. Abbreviations: CI: confidence interval; CNKI: China National Knowledge Infrastructure Database; CSTJ, China Science and Technology Journal Database; NOS: the Newcastle-Ottawa Scale; PRISMA: preferred reporting items for systematic reviews and meta-analyses; RCT: randomized controlled trial; RoB: the cochrane risk-of-bias; RD: risk difference; WMD: weighted mean difference; SE: standard error; SND: standard normal deviate.

Effect of Carboxymethyl Chitin on Capsule Formation around Silicone Implants: An In Vivo and In Vitro Study

BACKGROUND

Capsular contracture is a serious complication that occurs after augmentation mammaplasty. The authors previously identified that carboxymethyl chitin had an inhibitory effect on capsule formation. This study was performed to elucidate the possible molecular mechanisms through which carboxymethyl chitin inhibits the formation of a capsule around silicone implants.

METHODS

In this study, the authors cultured human dermal fibroblasts and treated them with carboxymethyl chitin in vitro. The difference in proliferation between treated and untreated cells was analyzed through the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Protein levels of transforming growth factor beta-1 and alpha smooth muscle actin (α-SMA) were examined by Western blot analysis. Expression levels of type I and type III collagen were checked by enzyme-linked immunosorbent assay. In vivo, silicone implants were placed under the pectoralis muscle in 12 female rabbits. The thickness of the capsule was measured by histologic analysis, and the effect of carboxymethyl chitin on α-SMA, collagen type I and III expression levels was evaluated by real-time polymerase chain reaction analysis, enzyme-linked immunosorbent assay, Western blot, and immunofluorescence analysis.

RESULTS

In the in vitro study, we confirmed that carboxymethyl chitin inhibited the proliferation of fibroblasts. The protein expression levels of collagen type I, transforming growth factor beta-1, and α-SMA were inhibited by carboxymethyl chitin treatment. In vivo, carboxymethyl chitin treatment reduced capsular thickness and the expression of α-SMA and collagen types I and III in capsules around silicone implants.

CONCLUSION

The authors' results showed that carboxymethyl chitin could influence capsule formation around silicone implants by inhibiting the fibroblast activity, interrupting fibroblast-to-myofibroblast differentiation, and decreasing collagen synthesis.

CLINICAL RELEVANCE STATEMENT

Carboxymethyl chitin influence capsule formation around silicone implants. Although more clinical studies are needed to verify the effect of carboxymethyl chitin on capsular contracture, the authors believe that it will play an effective role in the clinical application of reducing the occurrence of capsular contracture.

AGO Recommendations for the Surgical Therapy of Breast Cancer: Update 2022

The recommendations of the AGO Breast Committee on the surgical therapy of breast cancer were last updated in March 2022 (www.ago-online.de). Since surgical therapy is one of several partial steps in the treatment of breast cancer, extensive diagnostic and oncological expertise of a breast surgeon and good interdisciplinary cooperation with diagnostic radiologists is of great importance. The most important changes concern localization techniques, resection margins, axillary management in the neoadjuvant setting and the evaluation of the meshes in reconstructive surgery. Based on meta-analyses of randomized studies, the level of recommendation of an intraoperative breast ultrasound for the localization of non-palpable lesions was elevated to "++". Thus, the technique is considered to be equivalent to wire localization, provided that it is a lesion which can be well represented by sonography, the surgeon has extensive experience in breast ultrasound and has access to a suitable ultrasound device during the operation. In invasive breast cancer, the aim is to reach negative resection margins ("no tumor on ink"), regardless of whether an extensive intraductal component is present or not. Oncoplastic operations can also replace a mastectomy in selected cases due to the large number of existing techniques, and are equivalent to segmental resection in terms of oncological safety at comparable rates of complications. Sentinel node excision is recommended for patients with cN0 status receiving neoadjuvant chemotherapy after completion of chemotherapy. Minimally invasive biopsy is recommended for initially suspect lymph nodes. After neoadjuvant chemotherapy, patients with initially 1 - 3 suspicious lymph nodes and a good response (ycN0) can receive the targeted axillary dissection and the axillary dissection as equivalent options.

Pharmacological Approaches for the Prevention of Breast Implant Capsular Contracture

Capsular contracture is a common complication associated with breast implants following reconstructive or aesthetic surgery in which a tight or constricting scar tissue capsule forms around the implant, often distorting the breast shape and resulting in chronic pain. Capsulectomy (involving full removal of the capsule surrounding the implant) and capsulotomy (where the capsule is released and/or partly removed to create more space for the implant) are the most common surgical procedures used to treat capsular contracture. Various structural modifications of the implant device (including use of textured implants, submuscular placement of the implant, and the use of polyurethane-coated implants) and surgical strategies (including pre-operative skin washing and irrigation of the implant pocket with antibiotics) have been and/or are currently used to help reduce the incidence of capsular contracture. In this article, we review the pharmacological approaches-both commonly practiced in the clinic and experimental-reported in the scientific and clinical literature aimed at either preventing or treating capsular contracture, including (i) pre- and post-operative intravenous administration of drug substances, (ii) systemic (usually oral) administration of drugs before and after surgery, (iii) modification of the implant surface with grafted drug substances, (iv) irrigation of the implant or peri-implant tissue with drugs prior to implantation, and (v) incorporation of drugs into the implant shell or filler prior to surgery followed by drug release in situ after implantation.

Treatment and Prevention of Periprosthetic Capsular Contracture in Breast Surgery With Prosthesis Using Leukotriene Receptor Antagonists: A Meta-Analysis

BACKGROUND

Capsular contracture (CC) is the most common long-term complication of breast surgery with prosthesis. Leukotriene receptor antagonists (LRAs) have been tested as a potential treatment; however, mixed results have been observed.

OBJECTIVES

The aim of this study was to undertake a meta-analysis to clarify the treatment and prophylactic capabilities of LRAs in the management of CC.

METHODS

A systematic literature search of the most popular English-language databases was performed to identify relevant primary publications. We included all studies that used the Baker scale to evaluate the treatment and preventive capabilities of LRAs.

RESULTS

Six eligible studies were included based on predefined inclusion and exclusion criteria, totalling 2276 breasts, of which 775 did not receive LRAs and 1501 did. Final pooled results showed that LRAs could help manage CC with a risk difference (RD) of -0.38 with a corresponding 95% CI of -0.69 to -0.08, showing statistical significance at a Z value of 2.48, P = 0.01. Subgroup analysis based on the type of drug showed that only montelukast yielded statistical significance (RD = -0.27, 95% CI = -0.51 to -0.03, Z = 2.20, P = 0.03). Zafirlukast did not seem to influence CC. Further subgroup analysis based on treatment timing showed that prophylaxis was ineffective and only treatment for ongoing CC yielded statistically significant improvements.

CONCLUSIONS

The current meta-analysis proved that LRAs could be used in the management of CC. Only treatment for ongoing CC showed statistically significant improvements. Montelukast seemed to be more efficient with a safer profile for adverse effects, whereas zafirlukast yielded no statistically significant results.

LEVEL OF EVIDENCE: 4

A Case Report of Capsular Contracture Immediately Following COVID-19 Vaccination

Capsular contracture is fundamentally an immunological/inflammatory response to the implant, treating it as a foreign body in need of exclusion from the immune system. The capsule surrounding the implant is populated by a rich variety of immunologically active cells such as macrophages, T lymphocytes, and myofibroblasts. Vaccination in general and the COVID-19 vaccine in particular result in specific and nonspecific activation of the immune system, including those immune cells in proximity to the implant. This phenomenon has been previously demonstrated in delayed inflammatory reactions to previously implanted hyaluronic acid fillers following COVID-19 vaccination. This report is what is believed to be the first case of the rapid development of severe ipsilateral capsular contracture in the immediate aftermath of the second dose of the BNT162b2 (Pfizer) vaccine.

Comparison of the Incidence of Capsular Formation in Two-Stage, Implant-Based Breast Reconstruction Using an Insertion Funnel and Sizer

Purpose

Capsular formation around breast implants can produce various complications, including erythema, tenderness, discomfort, and breast deformation. Moreover, the capsule is thought to be correlated with breast implant-associated anaplastic large cell lymphoma. The proposed technique of capsule reduction can prevent some of these complications. Thus, the authors suggest a no-touch technique in two-stage, implant-based breast reconstruction. Patients and Methods. This single-center retrospective study evaluated the medical records and digitalized pathological slides of patients who underwent two-stage, implant-based breast reconstruction between February 2018 and May 2019. The selected patients were divided into group A and group B. Group A underwent a no-touch technique that included the following two steps: (1) using a sizer as the frame to create the submuscular and acellular dermal matrix (ADM) pocket for expander insertion and (2) inserting the expander through the funnel. After the second stage of implant insertion, the capsule was harvested for biopsy of the ADM, chest wall, and muscle.

Results

This study included 33 breasts (31 patients): 18 in group A and 15 in group B. The capsular thicknesses of the ADM, the chest wall, and the muscle of group A were significantly thinner than those in group B. Pearson's correlation coefficient indicated negative correlations between capsular thickness and age; underlying disease; lesion side; interval of two-stage implant insertion; size of the expander; and radiotherapy, chemotherapy, or hormone therapy.

Conclusion

To reduce the incidence of capsular formation following breast reconstruction using prostheses, a no-touch technique that uses a funnel and sizer to avoid implant contact is both efficient and beneficial.

Correction of Suboptimal Results in Implant-Based Breast Reconstruction

Implant-based breast reconstruction is the most common means to rebuild the breast following mastectomy. Although largely successful in restoring breast shape, suboptimal results may occur secondary to inadequate size or projection, malposition, rippling and contour irregularities, nipple malposition, capsular contracture, or implant rotation/flipping. This article reviews common strategies to improve implant reconstruction outcomes with revisional surgery.

LEVEL OF EVIDENCE: 4

Overview of Risk Factors and Prevention of Capsular Contracture Following Implant-Based Breast Reconstruction and Cosmetic Surgery: A Systematic Review

Capsular contracture is one of the most common complications of implant-based breast reconstruction or augmentation surgery. Despite advanced molecular biology, the exact mechanism of this complication is not fully understood. PubMed was searched for studies, published from 2015 to 2020, focused on potential risk factors and preventions of capsular contracture (CC) in patients who underwent implant-based breast surgery. A total of 533 articles were identified from PubMed, and 13 articles were selected ultimately for our review after eligibility screening and quality appraisal. Common risk factors of CC include biofilm, surgical site infections (SSI), history of prior CC or fibrosis, history of radiation therapy, and implant characteristics. Interventions that decrease the rate of CC include antibiotic prophylaxis or irrigation, acellular dermal matrix (ADM), leukotriene (LTE) inhibitors, surgical techniques, and others. Multiple risk factors are proposed to be a component of the pathophysiology of CC. However, there is inconsistent evidence supporting these risk factors, and the current data was based on broad heterogeneous studies. While efforts are being undertaken to solve this complication with improved technologies and surgical practices, CC remains to be unsolved. Our objective was to provide a summary of the current data of contributing risk factors as well as preventative and treatment measures for CC.

Montelukast Drug May Improve COVID-19 Prognosis: A Review of Evidence

With the lack of effective therapy, chemoprevention and vaccination, focusing on the immediate repurposing of existing drugs gives hope of curbing the pandemic. Interestingly, montelukast, a drug usually used in asthma, may be proposed as a potential adjuvant therapy in COVID-19. The aim of the present article was to review the properties of montelukast that could be beneficial in COVID-19. Ten experimentally supported properties were retrieved, either related to SARS-CoV-2 (antiviral properties, prevention of endotheliitis and of neurological disorders linked to SARS-CoV-2), and/or related to the host (improvement of atherogenic vascular inflammation, limitation of the ischemia/reperfusion phenomenon, improvement of respiratory symptoms), and/or related to serious COVID-19 outcomes (limitation of the cytokine storm, mitigation of acute respiratory distress syndrome), and/or related to tissue sequelae (antioxidant properties, anti-fibrosis effects). Based on gathered theoretical evidence, we argue that montelukast should be further tested to prevent and treat COVID-19 outcomes.