Acellular Dermal Matrices in Breast Surgery: A Comprehensive Review

Impact of Tumor Location on Aesthetic Outcomes in Oncoplastic Breast-Conserving Surgery: A Retrospective Comparison of Three Acellular Dermal Matrix Techniques

Background/Objectives: Oncoplastic breast-conserving surgery (OBCS) with acellular dermal matrix (ADM) has gained prominence in contemporary breast cancer management, yet evidence-based guidelines for selecting optimal ADM techniques based on the tumor location remain undefined. This investigation evaluated the impact of the tumor quadrant location and ADM application methodology on aesthetic outcomes, patient satisfaction, and postoperative complications following OBCS. Methods: This retrospective comparative analysis examined 229 patients who underwent OBCS with immediate ADM-based volume replacement (2020-2022) utilizing three distinct techniques: the diced ADM with sheet technique (n = 102), the diced ADM with paste-type micronized technique (n = 70), or the diced ADM-only technique (n = 57). The outcomes were stratified by tumor location (superomedial, superolateral, inferomedial, and inferolateral) and evaluated using validated physician-assessed aesthetic scores (four-point scale), patient satisfaction metrics, and comprehensive complication profiling with 24-month minimum follow-up. Results: The tumor quadrant location significantly influenced aesthetic outcomes across all techniques (p < 0.001), with superolateral quadrants demonstrating superior results (3.5 ± 0.4). In the superomedial quadrant, the diced ADM with paste-type micronized technique yielded significantly higher aesthetic scores than the diced ADM-only technique (3.2 ± 0.5 vs. 2.8 ± 0.6, p = 0.032, Cohen's d = 0.71). In the superolateral quadrant, the diced ADM-only technique achieved superior outcomes compared with the diced ADM with sheet technique (3.6 ± 0.4 vs. 3.4 ± 0.5, p = 0.020, d = 0.44). For inferomedial defects, the diced ADM with sheet technique demonstrated significant advantages over the diced ADM-only technique (2.9 ± 0.7 vs. 2.7 ± 0.7, p = 0.005, d = 0.29). A consistent discrepancy between physician and patient assessments was observed, particularly in medial quadrant reconstructions (mean difference: 0.2 points, p = 0.003). Conclusions: The optimal ADM technique varied significantly by tumor location. The diced ADM with paste-type micronized technique demonstrated superior outcomes in superomedial defects, the diced ADM with sheet technique provided essential structural support for inferomedial reconstructions, and the diced ADM-only technique achieved excellent results with reduced material requirements in superolateral locations. These findings provide preliminary evidence that may guide quadrant-specific ADM technique selection in OBCS, potentially enhancing aesthetic outcomes, patient satisfaction, and resource utilization.

Biologic Response With and Without Acellular Dermal Matrix in Breast Reconstruction

Background

Acellular dermal matrices (ADMs) are biologic meshes commonly used in implant-based breast reconstruction (IBBR) procedures to provide implant support and coverage. Although the etiology is not well understood, increasing preclinical and clinical evidence suggest that ADMs may help prevent capsular contracture, a frequent complication of IBBR, by modulating the inflammatory response in the tissue surrounding breast implants. The objective of this narrative review is to discuss the evidence supporting the role of inflammation in capsular contracture following IBBR without ADM, and to characterize the potential mechanism(s) by which ADMs may reduce the incidence of capsular contracture in IBBR.

Methods

Relevant studies in English published up to December 31, 2023, were identified from 4 databases (BIOSIS Previews, Embase, MEDLINE, and Northern Light Life Sciences Conference Abstracts) using search terms such as "breast" and "capsular contracture."

Results

This review discusses the potential factors (eg, expander-to-implant reconstruction, diminished collagen integrity, postmastectomy radiation therapy, surface of implant, plane of placement, incision type, hematoma, seroma, postoperative infection, and biofilm) and emerging biomarkers (eg, NRG1, IL-8, TIMP-1, TIMP-2, TIMP-4, MMP2, MMP12, ACAN, SAA1, TNFSF11, and hyaluronan) that may be able to predict capsular contracture. The available evidence that tissue integration of ADMs modulates the wound healing process and inflammation, and the available clinical evidence, which indicates that ADMs may decrease rates of capsular contracture following postmastectomy radiation therapy, are summarized.

Conclusions

The studies summarized in this review suggest that ADMs may reduce the likelihood of capsular contracture in IBRR compared with no ADM use.

Postmastectomy dual-plane submuscular-subcutaneous implant-based reconstruction: a series of 100 consecutive patients

BACKGROUND

Advances in cancer knowledge and surgical techniques over the last decades have enabled plastic surgeons to use muscle-sparing procedures and more conservative approaches for implant-based reconstructions. In this paper, the authors describe an innovative subpectoral/subcutaneous implant pocket that represents an evolution of the classical submuscular technique and they report on the first consecutive hundred patients undergoing this procedure.

METHODS

Between April 2019 and May 2022, 100 consecutive patients underwent immediate postmastectomy implant-based reconstruction using the subpectoral/subcutaneous space, for a total of 122 procedures. Medical records were retrospectively reviewed and patients were prospectively followed. During plastic consultations, medical photographs were taken and aesthetic outcomes were scored with patients.

RESULTS

Mean follow-up was 18 months (range 6-46). Implant loss was observed in two patients (2%). Early minor complications were registered in 19 patients. A total of 80 out of 100 patients completed satisfaction survey assessing their postoperative outcomes. Results were considered satisfactory or very satisfactory by the surgeons and patients in more than 90% of cases.

CONCLUSION

The submuscular/subcutaneous pocket can be considered a new tool in the armamentarium of reconstructive procedures, in between submuscular/subfascial procedures and prepectoral ones. It is a one-stage procedure, its a simple and short time surgery, reproducible, its very well accepted by patients. It has specific indications, advantages, and drawbacks, a careful indication and an accurate surgical technique are mandatory to achieve good results.

A Cohort Analysis of Early Outcomes After AlloDerm, FlexHD, and SurgiMend Use in Two-Stage Prepectoral Breast Reconstruction

BACKGROUND

Acellular dermal matrix (ADM) is frequently utilized in prepectoral breast reconstruction, but few studies have examined the role of ADM type in complication risk.

OBJECTIVES

This study was performed to determine the impact of ADM type on early complication rates in 2-stage alloplastic prepectoral breast reconstruction.

METHODS

We performed a cohort examination of all patients who underwent mastectomy with immediate 2-stage alloplastic prepectoral breast reconstruction with ADM support at Memorial Sloan Kettering Cancer Center from 2018 to 2021. ADM types utilized included AlloDerm (LifeCell Corporation, Branchburg, NJ), FlexHD (MTF Biologics, Edison, NJ), and SurgiMend (Integra LifeSciences Corporation, Princeton, NJ). Complication rates based on the number of tissue expanders (TEs) were determined for each ADM type. Performance of multivariate logistic regression determined the impact of ADM type on complication risk after accounting for confounders.

RESULTS

Overall, 726 patients (1054 TEs: 194 AlloDerm, 93 FlexHD, 767 SurgiMend) were included. The 3 cohorts differed in terms of mastectomy type (nipple-sparing: 23.5% of AlloDerm, 33.3% of FlexHD, 19.1% of SurgiMend, P = .038); ADM perforation (perforated: 94.8% of AlloDerm, 98.2% of FlexHD, 100% of SurgiMend, P < .001); and ADM size (AlloDerm: 153.2 cm2 [37.6], SurgiMend: 198.7 cm2 [10.4], FlexHD: 223.7 cm2 [37.9], P < .001). On univariate examination, no differences existed between ADM types for seroma, infection, exposure, malposition, or TE loss. Additionally, after adjustment for confounders with multivariate regression, no ADM type had higher odds of TE loss.

CONCLUSIONS

In this large cohort of prepectoral reconstruction patients, ADM type did not significantly affect the risk of complications. Additional prospective studies are warranted to better evaluate ADM choice for prepectoral breast reconstruction.

LEVEL OF EVIDENCE: 4

Comparative clinical outcomes of using three-dimensional and TIGR mesh in immediate breast reconstruction surgery for breast cancer patients

INTRODUCTION

Breast reconstruction (BR) surgery is a widely utilized approach for women who have undergone mastectomy. Using synthetic mesh can offer advantages over other materials providing long-lasting support and natural-looking results. This study aims to compare the effectiveness of 3DMax™ mesh to TIGR mesh in BR surgery, providing clear information about the non-inferiority of 3DMax™ mesh to TIGR.

METHODS

This retrospective cohort study evaluates postoperative complications in breast cancer patients who underwent subcutaneous mastectomy with direct-to-implant immediate BR using silicone implants and either 3DMax™ mesh or TIGR® Matrix Surgical Mesh.

RESULTS

This study involved BR surgeries in 82 patients, including 57 surgeries in the 3D mesh group and 49 in the TIGR mesh group. The two groups had no significant differences regarding age, body mass index (BMI), cancer stage, or surgical complications. However, patients with neoadjuvant chemotherapy or radiotherapy had higher incidence rates of long-term complications than other patients. Patients with infection or partial necrosis had a heightened risk of implant loss.

CONCLUSION

The clinical results obtained in this study suggest that among synthetic meshes used in immediate BR, 3DMax™ is not inferior to TIGR Matrix Surgical Mesh regarding complications.

Outcomes of Abdominal Wall Reconstruction with a Bovine versus a Porcine Acellular Dermal Matrix: A Propensity Score-Matched Analysis

BACKGROUND

Abdominal wall reconstruction (AWR) is one of the most commonly performed procedures, yet large comparative studies comparing outcomes of AWR using bovine acellular dermal matrix (BADM) and porcine acellular dermal matrix (PADM) are lacking.

METHODS

In this retrospective cohort study of patients who underwent AWR from March of 2005 to June of 2019, the primary comparative outcome measure was hernia recurrence with BADM versus PADM. The secondary outcome was the incidence of surgical-site occurrence (SSO) and surgical-site infection. A propensity score matching approach was applied to compare the clinical outcomes between the two study groups.

RESULTS

The authors identified 725 patients who underwent AWR using BADM (50.5%) or PADM (49.5%). Their mean ± SD age was 59.8 ± 11.5 years, mean body mass index was 31.4 ± 6.7 kg/m 2 , and mean follow-up time was 42 ± 29 months. With propensity score matching, 219 matched pairs were identified. Hernia recurrence rates in BADM (11.4%) and PADM (13.7%) groups did not differ significantly ( P = 0.793). SSO (26.5% versus 29.2%; P = 0.518) and SSI (13.2% versus 11%; P = 0.456) rates did not differ significantly in the PADM and BADM groups, respectively. Conditional logistic regression model and marginal Cox proportional hazards regression model determined that type of acellular dermal matrix was not significantly associated with SSOs (adjusted OR, 1.11; 95% CI, 0.74 to 1.70; P = 0.589) or hernia recurrence (adjusted hazard ratio, 0.85; 95% CI, 0.50 to 1.42; P = 0.52).

CONCLUSIONS

Both BADMs and PADMs provide durable, long-term outcomes. The hernia recurrence and postoperative surgical complication rates were not significantly different between BADM and PADM.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Comparison of the Characteristics of Three Acellular Dermal Matrices Subjected to Distinct Processing Methods Using Five Types of Histochemical Staining

BACKGROUND

Acellular dermal matrix (ADM) is treated using various devitalization and aseptic processing methods. The processing effects on ADM were evaluated by histochemical tests.

METHODS

From January 2014 to December 2016, 18 patients [average age, 43.0 (range, 30-54) years] who underwent breast reconstruction with an ADM and tissue expander were prospectively enrolled. During the permanent implant replacement, a biopsy of the ADM was performed. We used three different human-derived products, namely, Alloderm®, Allomend®, and Megaderm®. Hematoxylin and eosin, CD68, CD3, CD31, and smooth muscle actin were used to evaluate the collagen structure, inflammation, angiogenesis, and myofibroblast infiltration. Each ADM was semi-quantitatively analyzed.

RESULTS

Significant differences in collagen degradation, acute inflammation, and myofibroblast infiltration were observed among the ADMs. Collagen degeneration (p<0.001) and myofibroblast infiltration (smooth muscle actin-positive, p=0.018; CD31-negative, p=0.765) were the most severe in Megaderm®. Acute inflammation, represented by CD68, was most severe in Alloderm® (p=0.024). Both radiation and freeze-drying treatment physically damaged the collagen structure. Collagen degeneration was most severe in Megaderm®, followed by Allomend® and Alloderm®. Since Alloderm® is treated using chemicals, an assessment of the chemical irritation is warranted.

CONCLUSIONS

The biopsy results were inconclusive. Therefore, to better interpret processing, more large-scale, serial, histochemical studies of each ADM are needed.

LEVEL OF EVIDENCE IV

This journal requires that authors 38 assign a level of evidence to each article. For a full 39 description of these Evidence-Based Medicine ratings, 40 please refer to the Table of Contents or the online 41 Instructions to Authors www.springer.com/00266 .

Evaluation of Xenograft Efficacy in Immediate Prosthesis-based Breast Reconstruction

The advent of acellular dermal matrix (ADM) has revolutionized prosthesis-based breast reconstruction. However, paucity of human cadaveric tissue has resulted in limitation of supply and increased associated costs, prompting concerted effort to identify xenograft alternatives. Although studies have examined the safety of Artia, a porcine-derived ADM, few have evaluated its clinical efficacy as soft tissue reinforcement. This study uniquely evaluates the clinical efficacy of Artia in implant-based breast reconstruction.

Evaluation of Paste-Type Micronized Acellular Dermal Matrix for Soft Tissue Augmentation: Volumetric and Histological Assessment in a Mouse Model

BACKGROUND

A biological injectable material, paste-type micronized acellular dermal matrix (ADM), has been proven effective in wound healing by filling defects through tissue replacement. This study aimed to compare the efficacy of paste-type micronized ADM on soft tissue augmentation with that of the conventional fillers in animal experiments.

METHODS

Two distinct paste-type micronized ADMs, which were mixed with distilled water (mADM) and gelatin (mADM+GEL), respectively, were compared with conventional fillers, hyaluronic acid (HA) and polymethyl methacrylate (COL+PMMA). Thus, four different types of fillers were each injected into the dorsum of nude mice to compare the volume retention and biocompatibility. During the 8-week experimental period, ultrasound and computed tomography (CT) images were obtained for volumetric analysis. Histological evaluation was performed using hematoxylin and eosin and CD 31 staining.

RESULTS

According to the CT images at week 8, the mADM and mADM+GEL showed a higher volume persistence rate of 113.54% and 51.12%, compared with 85.09% and 17.65% for HA and COL+PMMA, respectively. The 2-week interval ultrasound images revealed that the mADM showed a volume increase in width rather than in height, and an increase in height for HA did not vary much. Histological analysis showed marked fibrous invasion and neovascularization with the mADM and mADM+GEL compared to that of the conventional fillers.

CONCLUSIONS

Paste-type micronized ADM showed soft tissue augmentation with similar effectiveness to that of conventional fillers. Therefore, paste-type micronized ADM has potential as an alternative material for a soft tissue filler in tissue replacement.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. 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 .

Patient Reported Outcome Measures After Breast Augmentation - Using the BREAST-Q IS

PURPOSE

Cosmetic breast augmentation procedures are commonly performed breast device surgeries. The Australian Breast Device Registry (ABDR) administers a five-question patient reported outcome measure (PROM), the BREAST-Q Implant Surveillance module (BREAST-Q IS), to patients 1, 2 and 5 years after breast device surgery. The measure includes an open-ended question to add any comments. This study aimed to use the responses to this open-ended question to assess participants' experiences of breast devices 1 and 2 years after breast augmentation. The secondary objective was to identify emerging and important issues relating to breast augmentation and devices.

PATIENTS AND METHODS

This qualitative descriptive study was conducted using a randomly selected sample of 268 responses to the open-ended question in the BREAST-Q IS, from the ABDR database. These responses were from patients who underwent breast augmentation between 2015 and 2018. Comments were analyzed using conventional content analysis in NVivo 12.

RESULTS

Four major themes were identified: satisfaction following breast augmentation, dissatisfaction following breast augmentation, complications and breast symptoms following breast augmentation and other comments. Two dominant themes were regarding satisfaction (n = 112) with overall surgical outcome, medical team, and post-operative appearance and complications and breast symptoms (n = 177) following breast augmentation. Emerging issues identified were rippling of breast implants and breast implant illness (BII).

CONCLUSION

PROMs can be used to understand patients' perspectives on various aspects of their own surgical experiences. Participants provided responses regarding complications and breast symptoms experienced, and rippling of the breast implants and BII are emerging issues after breast augmentation.

Allograft vs Xenograft Bioprosthetic Mesh in Tissue Expander Breast Reconstruction: A Blinded Prospective Randomized Controlled Trial

BACKGROUND

With the increased use of acellular dermal matrix (ADM) in breast reconstruction, the number of available materials has increased. There is a relative paucity of high-quality outcomes data for use of different ADMs.

OBJECTIVES

The goal of this study was to compare the outcomes between a human (HADM) and a bovine ADM (BADM) in implant-based breast reconstruction.

METHODS

A prospective, single-blinded, randomized controlled trial was conducted to evaluate differences in outcomes between HADM and BADM for patients undergoing immediate tissue expander breast reconstruction. Patients with prior radiation to the index breast were excluded. Patient and surgical characteristics were collected and analyzed.

RESULTS

From April 2011 to June 2016, a total of 90 patients were randomized to a mesh group, with 68 patients (HADM, 36 patients/55 breasts; BADM, 32 patients/48 breasts) included in the final analysis. Baseline characteristics were similar between the 2 groups. No significant differences in overall complication rates were identified between HADM (n = 14, 25%) and BADM (n = 13, 27%) (P = 0.85). Similar trends were identified for major complications and complications requiring reoperation. Tissue expander loss was identified in 7% of HADM patients (n = 4) and 17% of BADM patients (n = 8) (P = 0.14).

CONCLUSIONS

Similar complication and implant loss rates were found among patients undergoing immediate tissue expander breast reconstruction with HADM or BADM. Regardless of what material is used, careful patient selection and counseling, and cost consideration, help to improve outcomes and sustainability in immediate breast reconstruction.

LEVEL OF EVIDENCE: 2

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.

Immediate prepectoral implant reconstruction using TiLOOP Bra Pocket results in improved patient satisfaction over dual plane reconstruction

BACKGROUND

Implant-based reconstruction accounts for the majority of breast reconstructive procedures performed in Australia. More recently, immediate prepectoral implant reconstruction using the TiLOOP Bra Pocket has gained popularity. This study compares post-surgical complications and patient-reported quality of life outcomes between immediate prepectoral and dual plane implant reconstruction.

METHODS

A retrospective study of 80 consecutive patients who underwent nipple-sparing mastectomies and immediate implant reconstruction was conducted. Implants were either completely covered with TiLOOP Bra and/or TiLOOP Bra Pocket (pfm medical, Cologne, Germany) and secured in the prepectoral space (prepectoral group) or placed in the subpectoral plane with inferolateral mesh coverage (dual plane group). Data surrounding patient demographics, clinical details and post-surgical outcomes were compared. Patient-related quality of life outcomes were assessed with the Breast-Q questionnaire.

RESULTS

A total of 80 patients (109 breasts) operated on between June 2016 and December 2018 were included. The prepectoral and dual plane groups comprised of 40 patients each, including 50 and 59 operated breasts, respectively. Post-operative complications were comparable with 11 (22%) overall complications in the prepectoral group and eight (14%) in the dual plane group (P = 0.313). Implant loss was uncommon with four (8%) cases in the prepectoral group and five (8.5%) in the dual plane group (P = 0.929). Patient-reported quality of life outcomes were superior after prepectoral reconstruction with patients reporting a significantly higher score in the satisfaction with breasts domain (68.9 versus 57.5; P = 0.036).

CONCLUSION

Immediate prepectoral implant reconstruction with the TiLOOP Bra Pocket was associated with improved patient satisfaction and demonstrated no difference in early post-operative outcomes.

Dual-Plane Retro-pectoral Versus Pre-pectoral DTI Breast Reconstruction: An Italian Multicenter Experience

Background

The use of conservative mastectomies has risen significantly during the last few years. The reconstructive choice of direct-to-implant reconstruction has become more practicable with modern mastectomy techniques. The initial trend in Italian centers was to use dual-plane hybrid reconstruction. However, a high level of complications has been registered. From 2015 onward, in our centers, a pre-pectoral approach has been adopted. The authors sought to describe the Italian trend to gradually discard the sub-pectoral technique with lower lateral pole coverage of the prosthesis using ADMs comparing it with the pre-pectoral approach with ADMs, without any muscle dissection, in terms of complication rates.

Materials and Methods

A multicenter retrospective clinical study was performed from January 2010 to June 2018. The enrolled patients were divided into two groups: Cases with an ADM-only coverage pre-pectoral reconstruction made up the first group (Group 1). Those with the retro-pectoral muscular position + ADM implant coverage comprised the second one (Group 2). Complications such as seroma, hematoma, wound dehiscence, surgical site infection, reconstruction failure, animation deformity and capsular contracture were recorded.

Results

We performed 716 direct-to-implant reconstructions: 509 were partially sub-pectoral and 207 were pre-pectoral. Minimum follow-up was 1 year. Incidence of complications was higher in dual-plane reconstructions. There were statistical significant differences in the rates of seroma and hematoma.

Conclusion

Using the pre-pectoral approach, the authors have experienced favorable aesthetics and superior clinical and functional outcomes. Retro-pectoral muscular ADM implant coverage has to be considered only in specific complicated second-stage surgeries.

Level of Evidence V

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.

Electronic supplementary material

The online version of this article (10.1007/s00266-020-01892-y) contains supplementary material, which is available to authorized users.

Global view of human protein glycosylation pathways and functions

Glycosylation is the most abundant and diverse form of post-translational modification of proteins that is common to all eukaryotic cells. Enzymatic glycosylation of proteins involves a complex metabolic network and different types of glycosylation pathways that orchestrate enormous amplification of the proteome in producing diversity of proteoforms and its biological functions. The tremendous structural diversity of glycans attached to proteins poses analytical challenges that limit exploration of specific functions of glycosylation. Major advances in quantitative transcriptomics, proteomics and nuclease-based gene editing are now opening new global ways to explore protein glycosylation through analysing and targeting enzymes involved in glycosylation processes. In silico models predicting cellular glycosylation capacities and glycosylation outcomes are emerging, and refined maps of the glycosylation pathways facilitate genetic approaches to address functions of the vast glycoproteome. These approaches apply commonly available cell biology tools, and we predict that use of (single-cell) transcriptomics, genetic screens, genetic engineering of cellular glycosylation capacities and custom design of glycoprotein therapeutics are advancements that will ignite wider integration of glycosylation in general cell biology.

Histopathological Study of Meshed Versus Solid Sheet Acellular Dermal Matrices in a Porcine Model

BACKGROUND

Acellular dermal matrices (ADMs) are commonly used to support implant-based breast reconstruction. However, there is little comparative data on the incorporation process of different ADMs, and the value of meshing or fenestration versus solid sheet has not been established, although early clinical data suggest seroma rates may be reduced. This was a preclinical assessment of the incorporation process at optimal conditions in a pig model.

METHODS

SurgiMend and AlloDerm matrices were implanted in subcutaneous pockets on the backs of 15-week-old female pigs. Half of the samples were meshed 1:2.5; the remainder was grafted as a fenestrated (SurgiMend) or solid sheet (AlloDerm). Tissues were harvested at 3 months. Histological slides were prepared for hematoxylin and eosin staining, and Masson trichrome and immunostaining with anticollagen type I fluorescein isothiocyanate stain. Histological parameters (inflammation, giant cell reaction, neovascularization, fibroplasias, and scar tissue formation) were graded blindly on a scale of 0 (no reaction) to 3 (severe reaction).

RESULTS

All explanted ADMs (SurgiMend, n = 23; AlloDerm, n = 20) were firmly incorporated within the host tissue. SurgiMend showed more fibroplasia (P = 0.029) compared with AlloDerm in meshed or solid sheet form. Meshed ADMs showed a trend toward increased inflammation (P = 0.074) and giant cell reaction (P = 0.053) compared with solid sheet/fenestrated ADM.

CONCLUSIONS

Meshing ADM may allow cells to populate matrices more rapidly, promoting integration compared with solid sheet ADMs. This study sets the histological basis for further clinical investigations, with the aim of demonstrating lower complication rates (and particularly reduced seroma formation) with meshed ADMs.

Medical Applications of Collagen and Collagen-Based Materials

Collagen and collagen-based materials have been successfully used in medicine for over 50 years. The number of scientific articles about the role of collagen in the construction of scaffolds for tissue engineering has risen precipitously in recent years. The review contains materials about historic and modern applications of collagen in medicine such as soluble collagen injections, solid constructs reconstructed from solution, and decellularized collagen matrices. The analysis of published data proves the efficacy of collagen material in the treatment of chronic wounds, burns, venous and diabetic ulcers, in plastic, reconstructive and general surgery, urology, proctology, gynecology, ophthalmology, otolaryngology, neurosurgery, dentistry, cardiovascular and bone and cartilage surgery, as well as in cosmetology. Further development of collagenoplasty requires addressing the problems of allergic complications, improvement of structure and maximizing therapeutic effects against pathological processes.

Utility and Outcomes of Imaging Evaluation for Palpable Lumps in the Postmastectomy Patient

OBJECTIVE. The objective of our study was to assess the utility of targeted breast ultrasound and mammography in evaluating palpable lumps in the mastectomy bed. MATERIALS AND METHODS. This retrospective study identified postmastectomy patients who presented for initial imaging evaluation of palpable lumps between January 2009 and December 2015. Clinical, imaging, and pathology results were reviewed. Surgical reconstruction type and percutaneous sampling data were collected. Patients were excluded if they had known malignancy at imaging presentation, if the palpable lump was not at the mastectomy site, or if there was less than 1 year clinical or imaging follow-up in the absence of biopsy. Each palpable site was assigned as a case, and analyses were performed at the case level. RESULTS. Among the 101 patients with a history of prophylactic or therapeutic mastectomy who presented during the study period, 118 palpable cases met the inclusion criteria. All 118 cases were evaluated with ultrasound and 43 with mammography. Among the 75 cases evaluated with ultrasound alone, nine cancers were detected. Among the 43 cases evaluated with both ultrasound and mammography, three cancers were sonographically detected, of which two were mammographically visible and one was mammographically occult. There were two false-negative ultrasound cases; both underwent sampling because of the level of clinical suspicion. In total, 14 palpable lumps in 12 patients were malignant, and 104 palpable lumps in 89 patients were nonmalignant. Targeted ultrasound yielded a negative predictive value (NPV) of 97% and a positive predictive value 2 of 27%. CONCLUSION. Our data suggest that targeted breast ultrasound, with its high NPV, should be the initial imaging test of choice for palpable lumps after mastectomy. Mammography yielded no additional cancers but was helpful in confirming benign diagnoses. The two false-negative ultrasound cases support palpation-guided sampling for imaging-occult and clinically suspicious palpable lumps.

Porcine Acellular Peritoneal Matrix in Immediate Breast Reconstruction: A Multicenter, Prospective, Single-Arm Trial

BACKGROUND

Use of biological implants such as acellular dermal matrices in tissue expander breast reconstruction is a common adjunct to submuscular implant placement. There is a paucity of published prospective studies involving acellular matrices. The authors sought to evaluate a porcine-derived acellular peritoneal matrix product for immediate breast reconstruction.

METHODS

A prospective, single-arm trial was designed to analyze safety and outcomes of immediate tissue expander-based breast reconstruction with a novel porcine-derived acellular peritoneal matrix surgical mesh implant. Twenty-five patients were enrolled in this industry-sponsored trial. Patient demographics, surgical information, complications, histologic characteristics, and satisfaction (assessed by means of the BREAST-Q questionnaire) were evaluated.

RESULTS

Twenty-five patients (44 breasts) underwent mastectomy with immediate breast reconstruction using tissue expanders with acellular peritoneal matrix. Sixteen reconstructed breasts experienced at least one complication (36 percent). Seroma and hematoma occurred in one of 44 (2.3 percent) and two of 44 breasts (4.6 percent), respectively. Wound dehiscence occurred in four of 44 breasts (9.1 percent). Three subjects experienced reconstruction failure resulting in expander and/or acellular peritoneal matrix removal (6.8 percent); all failures were preceded by wound dehiscence. Histologic analysis showed cellular infiltration and product resorption. Results of the BREAST-Q demonstrated a level of postoperative patient satisfaction consistent with results in the available literature.

CONCLUSIONS

Prepared porcine-derived acellular peritoneal matrix is a safe adjunct in immediate two-stage tissue expander-based breast reconstruction. Further studies are required to determine efficacy compared to current commercially available acellular matrices.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Immediate Implant-Based Breast Reconstruction with Acellular Dermal Matrix: A Comparison of Sterile and Aseptic AlloDerm in 2039 Consecutive Cases

BACKGROUND

Sterile ready-to-use acellular dermal matrix, introduced as an alternative to aseptic freeze-dried acellular dermal matrix for implant-based breast reconstruction, has been investigated in a limited number of studies. This study compared outcomes in implant-based breast reconstruction with ready-to-use and freeze-dried acellular dermal matrix.

METHODS

The authors analyzed patients undergoing implant-based breast reconstruction with either freeze-dried or ready-to-use acellular dermal matrix, including demographics, clinical variables, and outcomes. An a priori power analysis was performed and logistic regression modeling was used to quantify the effect of acellular dermal matrix on outcomes while controlling for potential confounders.

RESULTS

A total of 1285 consecutive patients undergoing 2039 immediate prosthetic breast reconstructions constituted the population: 612 (n = 910 breasts) with freeze-dried matrix and 673 (n = 1129 breasts) with ready-to-use acellular dermal matrix. The freeze-dried matrix cohort had a significantly higher rate of explantation compared with the ready-to-use matrix cohort (18.0 percent versus 12.0 percent; p = 0.0036), but surgical-site infection, wound dehiscence, mastectomy flap necrosis, seroma, and hematoma did not differ significantly between groups. On multivariate regression, patients undergoing reconstruction with freeze-dried matrix, compared to ready-to-use matrix, did not have higher odds of experiencing surgical-site infections (OR, 1.064; p = 0.7455), but did have higher odds of explantation (OR, 1.570; p = 0.0161). Tobacco use (OR, 2.809; p = 0.0002) and body mass index (OR, 1.054; p < 0.0001) were also independent predictors of explantation.

CONCLUSION

Immediate implant-based breast reconstruction with sterile ready-to-use acellular dermal matrix has a comparable overall safety profile and a lower rate of prosthetic explantations compared with aseptic freeze-dried acellular dermal matrix.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Long term effects of modern breast cancer surgery

Breast cancer surgery includes a wide array of surgical treatment options. Not only does it involve the oncologic excision of the breast cancer disease but it also involves the reconstruction of the breast. Surgical treatment options vary with regards to the size of the tumor relative to the size of the breast further complicated by the preferences of the patient and the ability of the available surgeon(s). The goal of this paper is to highlight major long-term effects, positive and negative, of modern breast cancer surgery.

A Meta-analysis of Studies Comparing Outcomes of Diverse Acellular Dermal Matrices for Implant-Based Breast Reconstruction

BACKGROUND

The current diversity of the available acellular dermal matrix (ADM) materials for implant-based breast reconstruction raises the issue of whether there are any differences in postoperative outcomes according to the kind of ADM used. The present meta-analysis aimed to investigate whether choice of ADM products can affect outcomes.

METHODS

Studies that used multiple kinds of ADM products for implant-based breast reconstruction and compared outcomes between them were searched. Outcomes of interest were rates of postoperative complications: infection, seroma, mastectomy flap necrosis, reconstruction failure, and overall complications.

RESULTS

A total of 17 studies met the selection criteria. There was only 1 randomized controlled trial, and the other 16 studies had retrospective designs. Comparison of FlexHD, DermaMatrix, and ready-to-use AlloDerm with freeze-dried AlloDerm was conducted in multiple studies and could be meta-analyzed, in which 12 studies participated. In the meta-analysis comparing FlexHD and freeze-dried AlloDerm, using the results of 6 studies, both products showed similar pooled risks for all kinds of complications. When comparing DermaMatrix and freeze-dried AlloDerm with the results from 4 studies, there were also no differences between the pooled risks of complications of the two. Similarly, the meta-analysis of 4 studies comparing ready-to-use and freeze-dried AlloDerm demonstrated that the pooled risks for the complications did not differ.

CONCLUSIONS

This meta-analysis demonstrates that the 3 recently invented, human cadaveric skin-based products of FlexHD, DermaMatrix, and ready-to-use AlloDerm have similar risks of complications compared with those of freeze-dried AlloDerm, which has been used for longer. However, as most studies had low levels of evidence, further investigations are needed.

Comparing the Outcome of Different Biologically Derived Acellular Dermal Matrices in Implant-based Immediate Breast Reconstruction: A Meta-analysis of the Literatures

Background:

Acellular dermal matrices (ADMs) have been used extensively in implant-based breast reconstruction. It was reported that due to the different sources and processing methods, the outcomes of ADMs in implant-based breast reconstructions are expected to differ. We designed this study to statistically analyze and discuss the outcome of 3 commonly used ADMs, Alloderm, Strattice, and Surgimend in implant-based breast reconstruction.

Methods:

Comprehensive review of the literatures searched on electronic databases was done to identify studies published between 2006 and 2017 comparing the outcome of ADMs. Pooled random effect estimates for each complication and 95% confidence interval (CI) were calculated. One-way analysis of variance and Bonferroni test were used to compare statistical significance between and within groups, respectively. Multiple linear regression was done to include confounding factors and R statistic program for forest plot.

Results:

Twenty-one studies met the inclusion with a total of 1,659, 999, and 912 breasts reconstructions in Alloderm, Strattice, and Surgimend, respectively. Seven complications extracted including major and minor infection, seroma, implant loss, hematoma, capsular contracture, and localized erythema. Pooled total complication rates were 23.82% (95% CI, 21.18–26.47%) in Strattice, 17.98% (95% CI, 15.49–20.47%) in Surgimend, 16.21% (95% CI, 14.44–17.99%) in Alloderm. Seroma rate was the highest in Strattice group (8.61%; 95% CI, 6.87–10.35%). There was no statistical significance between and within groups.

Conclusion:

Although Strattice exhibited a higher overall pooled complication rate compared with Alloderm and Surgimend, the incidence of individual complication varies between studies. A cost analysis of different ADMs may aid in choosing the type of ADMs to be used.

A 3D Mammometric Comparison of Implant-Based Breast Reconstruction With and Without Acellular Dermal Matrix (ADM)

This retrospective study utilizes 3D imaging and mammometrics to compare implant-based breast reconstruction with and without the use of ADM. Previous studies have suggested improved aesthetic outcomes with the use of ADM, but none have been able to quantify this difference. Images were obtained at early and late time points following the expander-implant exchange procedure. Measurements included the point of maximum projection, the superior, inferior, medial and lateral volumetric distribution, and the distance from the point of maximum projection to the inframammary fold along the breast meridian. The patients' demographic information, implant size, and complication rate between the two cohorts were similar. In the early post-operative period, the patients with ADM demonstrated higher medial pole volume; however, this difference did not persist in the late post-operative period. Patients with ADM demonstrated a small but statistically significant greater point of maximum projection and length of lower pole curvature in comparison with the non-ADM cohort. In summary, the results of this study demonstrate improved mammometric measurements when ADM is used in implant-based breast reconstruction, supporting superior aesthetic outcomes in early and late post-operative time points.

LEVEL OF EVIDENCE III

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 .

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.

Prepectoral Implant-Based Breast Reconstruction

Background:

The development of acellular dermal matrices (ADMs) has facilitated single-stage implant breast reconstruction (IBR) following skin-sparing mastectomy. The conventional approach of postpectoral implant placement with lower pole ADM confers a good cosmetic result by improving lower pole projection and control, while minimizing issues of implant visibility, palpability, and rippling. This is balanced with potential disadvantages including pain, disruption of pectoral muscle function, and animation. We report the results of a prospective study of prepectoral IBR with total ADM coverage.

Methods:

Prepectoral IBR with total ADM coverage was performed in 106 patients (166 breasts) in our institution from 2013 to 2017. The cohort included patients undergoing immediate IBR (113 breasts) and revision of existing submuscular IBR (53 breasts). Patient demographics, surgical complications, and outcomes from a prospective database were analyzed.

Results:

At a mean follow-up of 485 days, patient satisfaction and cosmetic outcomes have been good, with no significant capsular contractures or animation deformity. Minor complications including delayed healing, red breast, or seroma occurred in 14 breasts (8.4%). Major complications including necrosis and implant loss occurred in 5 breasts (3 patients), with a total explantation rate of 3%. No patients required more than an overnight stay in hospital, and there were no delays to adjuvant treatment in therapeutic cases.

Conclusion:

Prepectoral implant placement with ADM cover is emerging as an alternative approach for IBR. This method facilitates breast reconstruction with a good cosmetic outcome for patients who want a quick recovery without potential compromise of pectoral muscle function and associated problems.

Acellular Dermal Matrix (Permacol®) for Heterologous Immediate Breast Reconstruction after Skin-Sparing Mastectomy in Patients with Breast Cancer: A Single-Institution Experience and a Review of the Literature

OBJECTIVE

Skin-sparing mastectomy (SSM) with immediate heterologous reconstruction is a safe oncological option in surgical therapy of early breast cancer. Permacol^® is an acellular dermal matrix (ADM) placed between the implant and the skin to improve lower pole projection and implant coverage. The aim of our study was to evaluate the outcome with a focus on patient satisfaction after 6 months and to analyze physical changes of ADM.

METHODS

10 patients who underwent SSM with Permacol^® were analyzed retrospectively. All patients were followed using a satisfaction questionnaire and an ultrasound evaluation of the tissue thickness of the pectoralis muscle and the Permacol^®.

RESULTS

No intraoperative complications were observed. One patient required removal of the implant for necrosis after 3 months. Half of the patients underwent secondary corrective surgery. A statistically significant thinning of the pectoralis muscle was observed, compared to the thickening of the Permacol^®. A majority of the patients were satisfied with the operation, and we found a correlation between lower body mass index and patient satisfaction.

CONCLUSION

In our small case series Permacol^®-assisted immediate reconstruction is shown to be an option for selected cases. Physical changes of Permacol^® result in a symmetrical coverage of the implant, which may improve cosmetic outcome.

Biological and synthetic mesh use in breast reconstructive surgery: a literature review

Mesh use in surgical breast reconstruction is becoming increasingly common; however, there is still no consensus on whether synthetic matrices or biological matrices produce the best outcomes. This review analyses these outcomes, namely the differences in aesthetic outcomes, cost, and the rates of the most commonly reported complications.

The results indicate that breast reconstruction with a synthetic matrix produces comparable aesthetic outcomes to a biological matrix, with lower costs and complication rates. The individual results for complication rates show that biological matrixes are associated with lower infection rates and slightly lower capsular contracture, but higher haematoma rates, and slightly higher rates of skin necrosis and explantation—although many had post-op radiotherapy.

The majority of the studies evaluated used biological matrices, and there are no randomised controlled trials directly comparing the two types of meshes; definite conclusions cannot be drawn from the available evidence. The authors suggest that a randomised controlled trial comparing these outcomes in synthetic and biological matrix use is needed.

Use of human acellular dermal matrix during classic bladder exstrophy repair

INTRODUCTION

The extent of the abdominal wall defect in people with classic bladder exstrophy (CBE) varies, and can be extensive. In this study, human acellular dermis (HAD) was used to bridge the fascial gap, as an alternative to osteotomy, to support a fascial repair of the abdominal wall, and as a filler in selected cases of CBE.

OBJECTIVE

To demonstrate the efficacy of the employed techniques of using HAD within the bladder exstrophy population.

MATERIALS AND METHODS

The medical records of six males, born with CBE, and who had abdominal wall defects were reviewed. Two children, aged 6 and 8 years old, were referred from overseas with unrepaired bladder exstrophy plates and large abdominal wall defects (8 cm and 12 cm wide). Both had their bladders reconstructed, placed within the pelvis, and HAD was used to replace the absent abdominal wall (bridged repair) without the use of pelvic osteotomy. In three other patients, HAD reinforced the native fascial repair (bolster repair). In three patients, HAD also served as a filler for the abdominal depression that was present following initial staged repair. Where HAD was used for bridged or bolster repair, the edges of the allograft were extended 2-3 cm circumferentially beyond the perimeter of the abdominal wall defect.

RESULTS

All six patients healed well, without evidence of abdominal wall hernias at 1-3 years postoperatively. Functionally, each patient regained an appropriate level of abdominal wall strength. Two children successfully underwent a secondary procedure through the bridged allograft repair, as each required bladder neck reconstruction and bilateral ureteral reimplantation through the reconstructed abdominal wall. Continence was achieved in these two patients, with one child voiding at 2-hourly intervals and the second at 3-hourly intervals. One patient developed a urethral-cutaneous fistula, distant to location of the allograft. There were no associated wound complications.

CONCLUSIONS

In this series of patients born with classic bladder exstrophy, HAD acted as a biologic scaffold and allowed native cellular ingrowth and tissue remodeling. It served as an alternative to pelvic osteotomy in older patients with unrepaired CBE. The material reinforced a weak or potentially suboptimal fascial repair and filled a tissue gap, resulting in improved aesthetics. Given its ease of preparation and the lack of significant morbidity associated with its use, combined with the functional and esthetic results in the present series, HAD may be considered during delayed reconstruction of abdominopelvic tissues in people born with CBE.

Remodeling Characteristics and Collagen Distributions of Biologic Scaffold Materials Biopsied From Postmastectomy Breast Reconstruction Sites

OBJECTIVE

The study purpose was to evaluate the associations between patient characteristics and the histologic remodeling scores of acellular dermal matrices (ADMs) biopsied from breast reconstruction sites in the first attempt to generate a multivariable risk prediction model of nonconstructive remodeling. It was hypothesized that host characteristics and surgical site assessments predict the degree of graft remodeling for ADMs used during breast reconstruction.

METHODS

The ADMs were biopsied from the breast reconstruction sites of n = 62 patients during a subsequent breast procedure, stained with hematoxylin-eosin, and evaluated according to a semi-quantitative scoring system for remodeling characteristics (cell types, cell infiltration, extracellular matrix deposition, scaffold degradation, fibrous encapsulation, and neovascularization) and a mean composite score. Biopsies were stained with Sirius Red and Fast Green, and analyzed to determine the collagen I:III ratio. Based on univariate analyses between subject clinical characteristics and the histologic remodeling scores, cohort variables were selected for multivariable regression models using a P value of 0.20 or less.

RESULTS

The composite score model yielded 3 variables: pack-year history, corticosteroid use, and radiation timing (r pseudo = 0.81). The model for collagen I yielded 2 variables: corticosteroid use and reason for reoperation (r pseudo = 0.78). The model for collagen III yielded 1 variable: reason for reoperation (r pseudo = 0.35).

CONCLUSIONS

These preliminary results constitute the first steps in generating a risk prediction model that predicts the patients and clinical circumstances most likely to experience nonconstructive remodeling of biologic grafts used to reconstruct the breast.

Mesh versus acellular dermal matrix in immediate implant-based breast reconstruction - A prospective randomized trial

BACKGROUND

Comparative studies on the use of meshes and acellular dermal matrices (ADM) in implant-based breast reconstruction (IBBR) have not yet been performed.

METHODS

This prospective, randomized, controlled, multicenter pilot study was performed at four Austrian breast cancer centers. Fifty patients with oncologic or prophylactic indication for mastectomy and IBBR were randomized to immediate IBBR with either an ADM (Protexa(®)) or a titanized mesh (TiLOOP(®) Bra). Complications, failed reconstruction, cosmetic outcome, patients' quality of life and the thickness of the overlying tissue were recorded immediately postoperatively and 3 and 6 months after surgery.

RESULTS

48 patients participated in the study (Protexa(®) group: 23; TiLOOP(®) Bra group: 25 patients). The overall complication rate was 31.25% with similar rates in both groups (Protexa(®) group: 9 versus TiLOOP(®) Bra group: 6; p = 0.188). There was a higher incidence of severe complications leading to failed reconstructions with implant loss in the Protexa(®) group than in the TiLOOP(®) Bra group (7 versus 2; p < 0.0001). An inverted T-incision technique led to significantly more complications and reconstructive failure with Protexa(®) (p = 0.037, p = 0.012, respectively). There were no significant differences in patients' satisfaction with cosmetic results (p = 0.632), but surgeons and external specialists graded significantly better outcomes with TiLOOP(®) Bra (p = 0.034, p = 0.032).

CONCLUSION

This pilot study showed use of TiLOOP(®) Bra or Protexa(®) in IBBR is feasible leading to good cosmetic outcomes and high patient satisfaction. To validate the higher failure rates in the Protexa(®) group, data from a larger trial are required. NCT02562170.

Acellular dermal matrices in breast reconstructions - a literature review

During the last two decades, acellular dermal matrices (ADM) have been more widely used in reconstructive procedures i.e. breast reconstructions. Several, both synthetic and biologic products derived from human, porcine and bovine tissue, have been introduced. Until this point postoperative complications for the acellular dermal matrices, as a group, have been the main focus. The purpose of this literature review is to summarize the current knowledge on the each biologic product used in breast reconstructions, including product specific complication frequencies. A systematic search of the literature was performed in the PubMed and EMBASE databases, identifying 55 relevant articles, mainly evidence level III. AlloDerm seems to be associated with severe complicating matters in the reconstructive process compared to other products. This could be due to the higher number of investigating studies relative to the others. The surgical area faces certain challenges comparing results, due to surgical variance, the data collection and follow-up. More well-defined guidelines and more high-evidence randomized studies could increase the overall level of evidence in this area.

In vitro evaluation of decellularized ECM-derived surgical scaffold biomaterials

Decellularized extracellular matrix (ECM) biomaterials are increasingly used in regenerative medicine for abdominal tissue repair. Emerging ECM biomaterials with greater compliance target surgical procedures like breast and craniofacial reconstruction to enhance aesthetic outcome. Clinical studies report improved outcomes with newly designed ECM scaffolds, but their comparative biological characteristics have received less attention. In this study, we investigated scaffolds derived from dermis (AlloDerm Regenerative Tissue Matrix), small intestinal submucosa (Surgisis 4-layer Tissue Graft and OASIS Wound Matrix), and mesothelium (Meso BioMatrix Surgical Mesh and Veritas Collagen Matrix) and evaluated biological properties that modulate cellular responses and recruitment. An assay panel was utilized to assess the ECM scaffold effects upon cells. Results of the material-conditioned media study demonstrated Meso BioMatrix and OASIS best supported cell proliferation. Meso BioMatrix promoted the greatest migration and chemotaxis signaling, followed by Veritas and OASIS; OASIS had superior suppression of cell apoptosis. The direct adhesion assay indicated that AlloDerm, Meso BioMatrix, Surgisis, and Veritas had sidedness that affected cell-material interactions. In the chick chorioallantoic membrane assay, Meso BioMatrix and OASIS best supported cell infiltration. Among tested materials, Meso BioMatrix and OASIS demonstrated characteristics that facilitate scaffold incorporation, making them promising choices for many clinical applications. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 585-593, 2017.

Breast Reconstruction Using Contour Fenestrated AlloDerm: Does Improvement in Design Translate to Improved Outcomes?

Background:

Acellular dermal matrices are used in implant-based breast reconstruction. The introduction of contour fenestrated AlloDerm (Life-Cell, Branchburg, N.J.) offers sterile processing, a crescent shape, and prefabricated fenestrations. However, any evidence comparing reconstructive outcomes between this newer generation acellular dermal matrices and earlier versions is lacking.

Methods:

Patients undergoing implant-based breast reconstruction from 2010 to 2014 were identified. Reconstructive outcomes were stratified by 4 types of implant coverage: aseptic AlloDerm, sterile “ready-to-use” AlloDerm, contour fenestrated AlloDerm, or total submuscular coverage. Outcomes were compared with significance set at P < 0.05.

Results:

A total of 620 patients (1019 reconstructions) underwent immediate, implant-based breast reconstruction; patients with contour fenestrated AlloDerm were more likely to have nipple-sparing mastectomy (P = 0.0001, 0.0004, and 0.0001) and immediate permanent implant reconstructions (P = 0.0001). Those with contour fenestrated AlloDerm coverage had lower infection rates requiring oral (P = 0.0016) and intravenous antibiotics (P = 0.0012) compared with aseptic AlloDerm coverage. Compared with sterile “ready-to-use” AlloDerm coverage, those with contour fenestrated AlloDerm had similar infection outcomes but significantly more minor mastectomy flap necrosis (P = 0.0023). Compared with total submuscular coverage, those with contour fenestrated AlloDerm coverage had similar infection outcomes but significantly more explantations (P = 0.0001), major (P = 0.0130) and minor mastectomy flap necrosis (P = 0.0001). Significant independent risk factors for increased infection were also identified.

Conclusions:

Contour fenestrated AlloDerm reduces infections compared with aseptic AlloDerm, but infection rates are similar to those of sterile, ready-to-use AlloDerm and total submuscular coverage.

Does acellular dermal matrix really improve aesthetic outcome in tissue expander/implant-based breast reconstruction?

BACKGROUND

The expectation for improved results by women undergoing postmastectomy reconstruction has steadily risen. A majority of these operations are tissue expander/implant-based breast reconstructions. Acellular dermal matrix (ADM) offers numerous advantages in these procedures. Thus far, the evidence to justify improved aesthetic outcome has solely been based on surgeon opinion. The purpose of this study was to assess aesthetic outcome following ADM use in tissue expander/implant-based breast reconstruction by a panel of blinded plastic surgeons.

METHODS

Mean aesthetic results of patients who underwent tissue expander/implant-based breast reconstruction with (n = 18) or without ADM (n = 20) were assessed with objective grading of preoperative and postoperative photographs by five independent blinded plastic surgeons. Absolute observed agreement as well as weighted Fleiss Kappa (κ) test statistics were calculated to assess inter-rater variability.

RESULTS

When ADM was incorporated, the overall aesthetic score was improved by an average of 12.1 %. In addition, subscale analyses revealed improvements in breast contour (35.2 %), implant placement (20.7 %), lower pole projection (16.7 %), and inframammary fold definition (13.8 %). Contour (p = 0.039), implant placement (p = 0.021), and overall aesthetic score (p = 0.022) reached statistical significance. Inter-rater reliability showed mostly moderate agreement.

CONCLUSIONS

Mean aesthetic scores were higher in the ADM-assisted breast reconstruction cohort including the total aesthetic score which was statistically significant. Aesthetic outcome alone may justify the added expense of incorporating biologic mesh. Moreover, ADM has other benefits which may render it cost-effective. Larger prospective studies are needed to provide plastic surgeons with more definitive guidelines for ADM use.

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 .

Acellular Dermal Matrix in Reconstructive Breast Surgery: Survey of Current Practice among Plastic Surgeons

Background:

Acellular dermal matrices (ADMs) in plastic surgery have become increasingly popular particularly for breast reconstruction. Despite their advantages, questions exist regarding their association with a possible increased incidence of complications. We describe a collective experience of plastic surgeons’ use of ADMs in reconstructive breast surgery using an internet-based survey.

Methods:

Members of the American Society of Plastic Surgeons were recruited through voluntary, anonymous participation in an online survey. The web-based survey garnered information about participant demographics and their experience with ADM use in breast reconstruction procedures. After responses were collected, all data were anonymously processed.

Results:

Data were ascertained through 365 physician responses of which 99% (n = 361) completed the survey. The majority of participants were men (84.5%) between 51 and 60 years (37.4%); 84.2% used ADM in breast reconstruction, including radiated patients (79.7%). ADM use was not favored for nipple reconstruction (81.5%); 94.6% of participants used drains, and 87.8% administered antibiotics postoperatively. The most common complications were seroma (70.9%) and infection (16%), although 57.4% claimed anecdotally that overall complication rate was unchanged after incorporating ADM into their practice. High cost was a deterrent for ADM use (37.5%).

Conclusions:

Plastic surgeons currently use ADM in breast reconstruction for both immediate and staged procedures. Of those responding, a majority of plastic surgeons will incorporate drains and use postoperative antibiotics for more than 48 hours.

Sterile acellular dermal collagen as a treatment for rippling deformity of breast

Prosthetic implants are frequently used for breast augmentation and breast reconstruction following mastectomy. Unfortunately, long-term aesthetic results of prosthetic breast restoration may be hindered by complications such as rippling, capsular contracture, and implant malposition. The advent of use of acellular dermal matrices has greatly improved the outcomes of prosthetic breast reconstruction. We describe a case of rippling deformity of breast that was treated using an acellular dermal matrix product, AlloMax. The patient presented with visible rippling of bilateral prosthetic breast implants as well as significant asymmetry of the breasts after multiple excisional biopsies for right breast ductal carcinoma in situ. A 6 × 10 cm piece of AlloMax was placed on the medial aspect of each breast between the implant and the skin flap. Follow-up was performed at 1 week, 3 months, and 1 year following the procedure. The patient recovered well from the surgery and there were no complications. At her first postoperative follow-up the patient was extremely satisfied with the result. At her 3-month and 1-year follow-up she had no recurrence of her previous deformity and no new deformity.

TiLoop® Bra mesh used for immediate breast reconstruction: comparison of retropectoral and subcutaneous implant placement in a prospective single-institution series

BACKGROUND

Immediate implant reconstruction after a conservative mastectomy is an attractive option made easier by prosthetic devices. Titanized polypropylene meshes are used as a hammock to cover the lower lateral implant pole. We conducted a prospective nonrandomized single-institution study of reconstructions using titanium-coated meshes either in a standard muscular mesh pocket or in a complete subcutaneous approach. The complete subcutaneous approach means to wrap an implant with titanized mesh in order to position the implant subcutaneously and spare muscles.

METHODS

Between November 2011 and January 2014, we performed immediate implant breast reconstructions after conservative mastectomies using TiLoop® Bra, either with the standard retropectoral or with a prepectoral approach. Selection criteria included only women with normal Body Mass Index (BMI), no large and very ptotic breasts, no history of smoking, no diabetes, and no previous radiotherapy. We analyzed short-term outcomes of such procedures and compared the outcomes to evaluate implant losses and surgical complications.

RESULTS

A total of 73 mastectomies were performed. Group 1 comprised 29 women, 5 bilateral procedures, 34 reconstructions, using the standard muscular mesh pocket. Group 2 comprised 34 women, 5 bilateral procedures, 39 reconstructions with the prepectoral subcutaneous technique. Baseline and oncologic characteristics were homogeneous between the two groups. After a median follow-up period of 13 and 12 months, respectively, no implant losses were recorded in group 1, and one implant loss was recorded in group 2. We registered three surgical complications in group 1 and two surgical complications in group 2.

CONCLUSIONS

Titanium-coated polypropylene meshes, as a tool for immediate definitive implant breast reconstruction, resulted as safe and effective in a short-term analysis, both for a retropectoral and a totally subcutaneous implant placement. Long-term results are forthcoming. A strict selection is mandatory to achieve optimal results. Level of Evidence: Level II, therapeutic study.

Biological Matrices and Synthetic Meshes Used in Implant-based Breast Reconstruction - a Review of Products Available in Germany

While autologous breast reconstruction was considered the procedure of choice for immediate breast reconstruction, there has been a shift towards implant-based breast reconstruction (IBBR) in recent years. The proven safety of silicone breast implants and the development of biological matrices and synthetic meshes have contributed to the growing popularity of this approach. Although these different products are widely used, only limited clinical data are available with regard to breast surgery. The aim of this review was to give an overview of available biological matrices and synthetic meshes and discuss their use in clinical practice.