Comparison of Histological Characteristics of Acellular Dermal Matrix Capsules to Surrounding Breast Capsules in Acellular Dermal Matrix–Assisted Breast Reconstruction

Implant-Based Breast Reconstruction after Risk-Reducing Mastectomy in BRCA Mutation Carriers: A Single-Center Retrospective Study

Women with BRCA gene mutations have a higher lifetime risk of developing breast cancer. Furthermore, cancer is usually diagnosed at a younger age compared to the wild-type counterpart. Strategies for risk management include intensive surveillance or risk-reducing mastectomy. The latter provides a significant reduction of the risk of developing breast cancer, simultaneously ensuring a natural breast appearance due to the preservation of the skin envelope and the nipple-areola complex. Implant-based breast reconstruction is the most common technique after risk-reducing surgery and can be achieved with either a submuscular or a prepectoral approach, in one or multiple stages. This study analyzes the outcomes of the different reconstructive techniques through a retrospective review on 46 breasts of a consecutive, single-center case series. Data analysis was carried out with EpiInfo version 7.2. Results of this study show no significant differences in postoperative complications between two-stage tissue expander/implant reconstruction and direct-to-implant (DTI) reconstruction, with DTI having superior aesthetic outcomes, especially in the prepectoral subgroup. In our experience, the DTI prepectoral approach has proven to be a safe and less time-consuming alternative to the submuscular two-stage technique, providing a pleasant reconstructed breast and overcoming the drawbacks of subpectoral implant placement.

Comparison of Cromolyn Sodium, Montelukast, and Zafirlukast Prophylaxis for Capsular Contracture

BACKGROUND

Capsular contracture is the most common complication following breast augmentation. Recently, prophylaxis studies aiming to inhibit the release of profibrotic substances to prevent capsular contracture have gained in importance. This study investigated the effects of cromolyn sodium, montelukast, and zafirlukast on capsular contracture in a rat model.

METHODS

Thirty female Wistar albino rats were randomly divided into five groups: control, sham, cromolyn sodium, montelukast, and zafirlukast. Intraperitoneal injections were administered daily to the sham (1 ml per day), cromolyn sodium (10 mg/kg per day), montelukast (10 mg/kg per day), and zafirlukast (1.25 mg/kg per day) groups 1 month before surgery. Miniature breast implants were then placed on the backs of the rats in each group. Injections were continued for the next 3 months. The rats were subsequently killed, and the capsules were harvested and assessed histopathologically. The histopathologic outcomes were acute inflammation status, inflammation severity, synovial metaplasia, foreign body reaction, mast cell count, and capsular thickness.

RESULTS

The cromolyn sodium, montelukast, and zafirlukast groups had less acute inflammation and lower mean inflammation severity scores, foreign body reaction occurrence, mast cell counts, and capsular thickness than the control and sham groups ( p < 0.05). These parameters were better in the cromolyn sodium group than in the montelukast and zafirlukast groups ( p < 0.05).

CONCLUSIONS

Cromolyn sodium appears to inhibit capsular contracture more efficiently than montelukast and zafirlukast. This report may be a pioneer study for the prophylactic use of cromolyn sodium in capsular contracture.

CLINICAL RELEVANCE STATEMENT

The prophylactic administration of cromolyn sodium appears to reduce capsular contracture more efficiently than that of montelukast and zafirlukast. This report might constitute a pioneer study for the prophylactic use of cromolyn sodium in capsular contracture.

Biological Cover Mitigates Disruption of the Dermal Structure in Mechanically Expanded Skin in a Porcine Model

Tissue expansion is an integral procedure of the vast majority of breast reconstruction and has a significant impact on the final clinical outcomes. Therefore, technological advances leading to a fewer number of unfavorable outcomes and a decrease in complication rates are imperative. In this study, using a porcine model, we investigated an effect of acellular dermal matrix (ADM) used as a tissue expander cover on the dermal changes induced by mechanical forces during tissue expansion. After 14 days of expansion, skin samples were collected from one animal, while the second animal underwent radiation, and tissue was collected 8 weeks later. Tissue expanded without the use of ADM and unexpanded skin served as the controls. Collected skin biopsies were used for histological and immunohistochemical evaluation, and for gene expression analysis. We revealed that the biological cover incorporation into host tissue is facilitated by macrophages without inducing a broad inflammatory response. The utilization of ADM mitigated disruption in the dermal structure, excessive collagen deposition, and capsule formation in non-irradiated expanded skin. The protective effect was not fully maintained in irradiated skin. These results demonstrate that tissue expansion might be improved by using the tissue expander cover.

Complete Implant Wrapping with Porcine-Derived Acellular Dermal Matrix for the Treatment of Capsular Contracture in Breast Reconstruction: A Case-Control Study

Background

Capsular contracture (CC) represents one of the most common complications in breast reconstruction surgery, impairing final result and patients’ well-being. The role of acellular dermal matrixes (ADM) has been widely described for the treatment and prevention of contracture. The aim of the study was to evaluate the efficacy and safety of complete implant coverage with porcine-derived ADM in preventing CC limiting complications. In addition, patients’ reported outcomes were evaluated in order to define the role of ADM in improving sexual, physical and psychosocial well-being and satisfaction.

Methods

42 patients who underwent surgical treatment of 46 contracted reconstructed breasts from May 2018th to May 2019th were collected in the two groups (ADM group vs. Control group).

Results

The ADM group showed lower rate of CC recurrence and a higher rate of implant losses and minor complications. A significant difference was observed in red breast syndrome (27.3% in the ADM group vs. absent in control the group) and skin ulceration rates (18.2% in the ADM group vs. 4.18% in the control group). As for patients’ perceived outcomes, the ADM group showed a statistically significant higher postoperative Satisfaction of Breast Scale score compared to the control group. In addition, a significant difference was observed in the improvement of Physical Well-Being of the Chest Scale and the Satisfaction of Breast Scale after surgery, in favor to the ADM group.

Conclusion

Complete implant coverage with ADM may reduce the risk of CC recurrence in breast reconstruction. An accurate patient selection allows minimizing complications improving patient well-being and satisfaction.

Level of Evidence IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

From Salvage to Prevention: A Single-Surgeon Experience with Acellular Dermal Matrix and Infection in Prepectoral Breast Reconstruction

BACKGROUND

Increasing amounts of acellular dermal matrix are being used with the adoption of prepectoral breast reconstruction. Postoperative infection remains a challenge in breast reconstruction, and the contribution of acellular dermal matrix type, processing, and sterility assurance level to risk of complications in prepectoral reconstruction is not well studied.

METHODS

The authors performed a retrospective review of patients who underwent immediate prepectoral breast reconstruction from February of 2017 to July of 2020. Because of an increase in the rate of infection, the drain protocol was changed and acellular dermal matrix type was switched from AlloDerm (sterility assurance level, 10-3) to DermACELL (sterility assurance level, 10-6) in January of 2019. Demographic and surgical variables were collected, in addition to details regarding development and management of infection.

RESULTS

Despite higher rates of direct-to-implant reconstruction and bilateral procedures and increased implant volumes, the rate of infection was significantly lower in patients who received DermACELL instead of AlloDerm [two of 38 (5.3 percent) versus 11 of 41 (26.8 percent); p = 0.014]. Drain duration was slightly longer in the DermACELL group, consistent with the change in drain protocol. Baseline demographic and clinical characteristics remained similar between the two groups.

CONCLUSIONS

With increased reliance on large amounts of acellular dermal matrix for prepectoral breast reconstruction, it directly follows that the properties of acellular dermal matrix with respect to incorporation, sterility, and implant support are that much more important to consider. There have been few studies comparing different types of acellular dermal matrix in prepectoral breast reconstruction, and further research is required to determine the contribution of acellular dermal matrix type and processing techniques to development of postoperative infection.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Current Concepts in Capsular Contracture: Pathophysiology, Prevention, and Management

Over 400,000 women in the United States alone will have breast implant surgery each year. Although capsular contracture represents the most common complication of breast implant surgery, surgeons continue to debate the precise etiology. General agreement exists concerning the inflammatory origin of capsular fibrosis, but the inciting events triggering the inflammatory cascade appear to be multifactorial, making it difficult to predict why one patient may develop capsular contracture while another will not. Accordingly, researchers have explored many different surgical, biomaterial, and medical therapies to address these multiple factors in an attempt to prevent and treat capsular contracture. In the current paper, we aim to inform the reader on the most up-to-date understanding of the pathophysiology, prevention, and treatment of capsular contracture.

Direct comparison of CGCRYODERM and DermACELL in the same patient for outcomes in bilateral implant-based breast reconstruction: a retrospective case series

Background

The use of acellular dermal matrix (ADM) has been popularized in implant-based breast reconstruction (IBR). However, it is still controversial if ADM-associated complication rates differ with varying types of ADM products. The aim of this study was to compare postoperative complications between CGCRYODERM and DermACELL.

Methods

A retrospective chart review was performed on 32 patients (64 breasts) who underwent bilateral prosthetic breast reconstruction between June 2015 and December 2019. All patients received two different ADMs in each breast during the surgery. Demographic variables, operative characteristics, and postoperative outcomes were compared between the cryopreserved and pre-hydrated ADM.

Results

The overall major and minor postoperative complications developed in 7 and 1 out of 32 patients, respectively. Seroma and infection were the most common complications. There were no cases that infection and/or seroma involved both breasts in one individual. No significant differences were observed in terms of seroma, infection, hematoma, mastectomy flap necrosis, or drainage period between the CGCRYODERM and DermACELL groups (P=0.5637, 0.1797, 1.0000, 0.3173, and 0.2925, respectively). There was no case of reconstruction failure leading to explantation.

Conclusions

There were no statistically significant differences in postoperative complications between the two breasts reconstructed with CGCRYODERM and DermACELL in the same patient who underwent bilateral IBR. This is the first study to compare cryopreserved and pre-hydrated ADMs. We suggest that CGCRYODERM is a suitable option with a comparable safety profile for IBR.

Comparison of inflammatory response and synovial metaplasia in immediate breast reconstruction with a synthetic and a biological mesh: a randomized controlled clinical trial

The aim of this study was to compare inflammatory response and synovial metaplasia in implant-based immediate breast reconstruction with a biological mesh (Veritas^®) with that of a synthetic mesh (TIGR^® Matrix Surgical Mesh). We hypothesize that the inflammatory response and formation of synovial metaplasia might be different and the rate of capsular contracture therefore different. The patients were recruited from the Gothenburg TIGR^®/Veritas^® Study (ClinicalTrials.Gov identifier NCT02985073). All referrals for bilateral immediate breast reconstruction were assessed for inclusions. During the operation, the patients were randomized to which sides the biological and the synthetic mesh were going to be applied. During the implant exchange biopsies were taken. Biopsies were taken from 30 breasts in 15 patients. There seem to be more myofibroblast and neovascularization in the biological meshes than in the synthetic and the collagen fibers seem to be aligned in an irregular pattern with both parallel and vertical fibers. In the synthetic meshes, there were more giant cells and foreign body reaction and the collagen fibers were loosely and well aligned, oriented parallel to the surface of the implant. Synovial metaplasia was seen in the majority of both the biological and the synthetic meshes. The histological patterns in early capsules from biological and synthetic meshes vary considerably. Nonetheless, it is unknown what role different cell types have in capsular formation in the long run and there was no difference in clinical capsular contracture at the clinical follow-up in this study.

Evidence for the Use of Acellular Dermal Matrix in Implant-Based Breast Reconstruction

Acellular dermal matrices (ADMs) are tissue grafts that have been specially processed to remove all cellular components. These machined biological scaffolds have become popular in a variety of surgical settings due to their rapid incorporation into living tissue. As ADMs are highly malleable and cause minimal inflammation, they have come to serve as a useful tool in implant-based breast reconstruction procedures. The major benefits of using an ADM in this setting include superior initial breast contouring, decreased risk of capsular contracture after implant insertion, and consistent sustained positioning of the reconstructed breast. Despite these advantages, these tissue grafts are foreign to the host, and postoperative complications following ADM insertion, including infection and seroma, have been well documented. When considering using ADMs in this setting, it is important to first consider patient-specific factors that could preclude their use, such as low body mass index, small breasts, or a history of radiation exposure to the breast tissue. ADM grafts are also expensive, which may present another barrier to their use. Review of the literature ultimately suggests a continued role for ADMs in implant-based breast reconstruction, and continued research in this field is warranted.

A potential dermal substitute using decellularized dermis extracellular matrix derived bio-ink

Upon bioprinting, cells are mixed with a biomaterial to fabricate a living tissue, thus emphasizing the importance of biomaterials. The biomaterial used in this study was a bio-ink prepared using skin decellularized extracellular matrix (dECM). Skin dECM was extracted by treating the dermis with chemicals and enzymes; the basic structural and functional proteins of the ECM, including collagen, glycosaminoglycans (GAGs), bioreactive materials and growth factors, were preserved, whereas the resident cells that might cause immune rejection or inflammatory responses were removed. The bio-ink based on dECM powder, together with human dermal fibroblasts (HDFs), was loaded into the nozzle of the 3D bioprinter to create the 3D construct. This construct underwent gelation with changing temperature while its shape was maintained for 7 days. The cells showed over 90% viability and proliferation. By analysing the gene expression pattern in the cells of the construct, the skin regenerative mechanism of the bio-ink was verified. Microarray results confirmed that the gene expression related to skin morphology and development had been enhanced because the bioreactive molecules and growth factors, in addition to residual ECM in dECM, provided an optimal condition for the HDFs.

A retrospective review of breast reconstruction outcomes comparing AlloDerm and DermaCELL

Acellular dermal matrix (ADM) has become an accepted and advantageous adjunct to alloplastic breast reconstruction. The increase in demand has led to an upsurge of dermal-based products, both human and animal derived. There are few direct ADM comparative studies, but it is unclear whether there are any differences in complication rates. Our primary objective was to determine whether there is a difference in outcomes between AlloDerm and DermACELL in immediate alloplastic breast reconstruction.

A retrospective chart review of those who underwent immediate alloplastic breast reconstruction from January to December 2016 was performed. This encompassed 64 consecutive patients (95 breasts) with tissue expander or direct-to-implant reconstruction and either AlloDerm or DermACELL ADM. Demographics, particulars of the surgery, additional treatments and complications were all recorded. Differences in seroma, haematoma and infection rates, as well as more serious complications including implant replacement, capsular contracture and failure, were all reviewed.

The groups were comparable in terms of age, BMI and relevant comorbidities. Mastectomy weight and resulting implant volume were higher in the DermACELL group, with volume reaching statistical significance (p = 0.001). With an average follow-up of 18 months, there was no difference in capsular contraction or implant replacement. However, in those who developed capsular contracture in the DermACELL group, more breasts had no history of radiation, which was significant (p = 0.042). Overall, there were no significant differences in complication rates of seroma, haematoma, mastectomy flap necrosis and infection.

The use of acellular dermal matrix in immediate two-stage prosthetic breast reconstruction provides protection from postmastectomy radiation therapy: a clinicopathologic perspective

Although there is ample evidence showing that radiation therapy increases the risk of complications of breast reconstruction, the efficacy of human acellular dermal matrix (CGCryoDerm®) in immediate tissue expander breast reconstruction in the setting of postmastectomy radiation therapy has not been fully elucidated. In this study, we report our institutional experience with pertinent refined surgical technique, and determine whether acellular dermal matrices have a protective effect in this increasingly prevalent clinical setting. Twenty-six patients who underwent immediate two-stage breast reconstruction in the setting of postmastectomy radiation therapy with at least 2 years of follow-up were retrieved. Fifteen patents were reconstructed with ADM, whereas 11 patients were reconstructed without ADM. The occurrence of complications was assessed according to the reconstruction type (with ADM vs without ADM). Furthermore, in patients reconstructed with ADM (n = 15), immunohistochemistry was performed to analyze the breast capsule with ADM compared with that without ADM in the same patient, according to the expression of alpha-smooth muscle actin (α-SMA). The occurrence of complications was significantly associated with the reconstruction type (with ADM vs. without ADM, p = 0.015). On the basis of the results of α-SMA staining, α-SMA+ myofibroblasts were relatively highly expressed throughout the breast capsule without ADM. On the contrary, α-SMA+ myofibroblasts present at the breast capsule adjacent to the ADM were scarce and irregularly scattered. Use of an acellular dermal matrix may be recommended to patients who are concerned about complications after immediate two-stage breast reconstruction in the setting of postmastectomy radiation therapy.

Moffitt Cancer Center Experience of Tissue Expander Breast Reconstruction: Does Acellular Dermal Matrix Increase Return to the Operating Room?

BACKGROUND

Tissue expander and implant remains the most common technique for breast reconstruction. A controversial topic within this method is routine use of acellular dermal matrix (ADM). Acellular dermal matrices have increased risks of infection, seroma, hematoma, skin flap necrosis, and total complications.

METHODS

After an institutional review board approval, a retrospective chart review was conducted of 756 tissue expander with implant cases from November 2010 to November 2016 at Moffitt Cancer Center with 2 breast reconstruction surgeons. Patients were grouped in 2 groups: tissue expander alone reconstruction (TE) and tissue expander with ADM (TE + ADM). Complications were defined by return visits to the operating room for irrigation and debridement as well as for subsequent tissue expander placement.

RESULTS

There were 703 patients in the TE group and 53 in the TE + ADM group. Patients undergoing TE + ADM reconstruction were 3 times more likely to experience return to operating room compared with patients undergoing TE alone (7.5% vs 2.4%). Patients were significantly more likely to undergo 3 or more subsequent tissue expander placement procedures with TE + ADM (54.7%) compared with TE alone (4.8%) (P < 0.0001).

CONCLUSIONS

Although ADM may be appropriate for specific patients, its use in tissue expander breast reconstruction should be judiciously selected, because there is an observed increase in complications needing return to the operating room.

Clinical Outcomes in Breast Reconstruction Patients Using a Sterile Acellular Dermal Matrix Allograft

BACKGROUND

Human acellular dermal matrices (ADMs) have enabled successful breast reconstructions while decreasing muscle donor morbidity and pain for the patient. However, some literature reports indicate an increase in complications, especially infection. The decellularization and terminal sterilization properties of DermACELL (D-ADM), a human ADM, may reduce the rate of complications in augmented breast reconstruction while still maintaining successful outcomes. In the study presented here, we evaluate the quality and safety of outcomes with the use of D-ADM during tissue expander breast reconstruction.

METHODS

A retrospective chart review was conducted of patients who underwent breast reconstruction with the use of D-ADM, at a single-military hospital-based practice, resulting in a population of 38 subjects and 58 breasts who had breast reconstruction augmented with D-ADM.

RESULTS

Fifty-six breasts (96.6%) in thirty-six patients demonstrated successful outcomes with a median 27 weeks' time to complete healing. Post-reconstruction radiation and chemotherapy were applied to 24.1 and 25.9% of reconstructions, respectively. Complications rates were minimal with rates of 1.7% for surgical site infection and 1.7% for red breast syndrome.

CONCLUSION

The low complication rates combined with the high success and patient satisfaction rates observed for D-ADM support the use of this ADM in breast reconstruction.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Biological incorporation of human acellular dermal matrix used in Achilles tendon repair

Human acellular dermal matrices (ADMs) are used successfully in a variety of procedures, including sports medicine related, wound repair, and breast reconstructions, but the mechanism of repair is still not fully understood. An opportunity to explore this mechanism presented itself when a patient experienced a rerupture of the native tendon due to a fall that occurred 2 months after undergoing an Achilles tendon repair using Matracell treated ADM. The ADM was removed and an extensive histology analysis was performed on the tissue. Additionally, a literature review was conducted to determine the mechanism of ADM integration into the tendon structure and explore if differences in this mechanism exist for different types of human ADMS. The histology analysis demonstrated that the healing process during a tendon reconstruction procedure is similar to that of wound healing. Furthermore, the literature review showed that differences exist in the mechanism for integration among various human ADMs and that these differences may be due to variances in the methods and technologies that manufactures use to process human ADMs.