Human acellular dermis increases surgical site infection and overall complication profile when compared with submuscular breast reconstruction: An updated meta-analysis incorporating new products✰

A Systematic Review and Meta-Analysis of Synthetic Mesh Outcomes in Alloplastic Breast Reconstruction

Background

Mesh implants are frequently employed in alloplastic breast reconstruction. Notably, no mesh to date has FDA approval for this indication. Several synthetic meshes have been introduced with heterogeneous properties and outcomes.

Objectives

This study aims to systematically review synthetic mesh use in alloplastic breast reconstruction, describe rates of short-term complications, and analyze these outcomes in reports comparing synthetic and biologic meshes. The authors hypothesized data from comparative and noncomparative studies would show no significant differences between synthetic and biological meshes.

Methods

The authors conducted a systematic literature review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Thirty-one studies reporting the use of synthetic mesh and clinical outcomes were included. Eight studies directly comparing synthetic mesh and biological mesh were meta-analyzed for relative risk (RR). Nineteen noncomparative studies were analyzed for meta-rates. Outcomes, including seroma, infection, reoperation, and explant, were assessed on a per-breast basis. Resultant models were challenged for sensitivity and bias.

Results

Meta-analysis of comparative studies demonstrated no difference in the risk of infection with synthetic mesh (RR = 0.53; 95% CI [0.26-1.10]), but a reduced risk of reoperation (RR = 0.54; 95% CI [0.33-0.89]) or explant (RR = 0.43; 95% CI [0.21-0.87]). Meta-analysis of noncomparative studies demonstrated rates of seroma = 3%; 95% CI [1%-6%], infection = 4%; 95% CI [3%-6%], reoperation = 10%; 95% CI [7%-13%], and explant = 3%; 95% CI [2%-5%]).

Conclusions

Studies comparing synthetic and biologic meshes demonstrated noninferiority of synthetic in all outcomes assessed. Noncomparative studies demonstrated rates of seroma, infection, reoperation, and explant similar to literature values for biological mesh.

Level of Evidence 2 Risk

Direct-to-Implant vs Tissue Expander Placement in Immediate Breast Reconstruction: A Prospective Cohort Study

BACKGROUND

Direct-to-implant (DTI) breast reconstruction after mastectomy has gained increasing popularity. While concerns over ischemic complications related to tension on the mastectomy flap persist, newer techniques and technologies have enhanced safety of this technique.

OBJECTIVES

To compare clinical and patient-reported outcomes of DTI and 2-stage tissue expander (TE) reconstruction.

METHODS

A prospective cohort design was utilized to compare the incidence of reconstructive failure among patients undergoing DTI and TE reconstruction by unadjusted bivariate and adjusted multivariable logistic regression analyses. Secondary clinical outcomes of interest included specific complications requiring intervention (infection, seroma, hematoma, mastectomy flap necrosis, incisional dehiscence, device exposure) and time to final drain removal. Patient-reported outcomes on BREAST-Q were also compared.

RESULTS

A total of 134 patients (257 breasts) underwent DTI reconstruction and 222 patients (405 breasts) received TEs. DTI patients were significantly younger with lower BMIs; less diabetes, hypertension, and smoking; and smaller breast sizes; they also underwent more nipple-sparing mastectomies with prepectoral reconstructions. Rates of any complication (18% DTI vs 24% TE, P = .047), reconstructive failure (5.1% vs 12%, P = .004), and seroma (3.9% vs 11%, P < .001) were significantly lower in the DTI cohort on unadjusted analyses; however, there were no significant differences on adjusted regressions. Patient-reported satisfaction with breasts, psychosocial well-being, and sexual well-being were more substantively improved with DTI reconstruction.

CONCLUSIONS

Prepectoral DTI reconstruction is a viable option for postmastectomy reconstruction in carefully selected patients, with no significant increase in reconstructive failure or other complications.

LEVEL OF EVIDENCE: 2

Review: Implant-Based Breast Reconstruction After Mastectomy for Breast Cancer: A Meta-analysis of Randomized Controlled Trials and Prospective Studies Comparing Use of Acellular Dermal Matrix (ADM) Versus Without ADM

BACKGROUND

Breast cancer is the world's most prevalent cancer, and many breast cancer patients undergo mastectomy as the choice of treatment, often with post-mastectomy breast reconstruction. Acellular dermal matrix (ADM) use has become a method to improve outcomes of reconstruction for these patients. We aimed to compare postoperative complications and patient-reported outcomes, which are still poorly characterized, between groups utilizing acellular dermal matrix during reconstruction and those without.

MATERIALS AND METHODS

We searched electronic databases from inception to 16 June 2022 for randomized controlled trials and prospective cohort studies comparing the outcomes of patients who have and have not received acellular dermal matrix in implant-based breast reconstruction. The results were quantitatively combined and analyzed using random-effects models.

RESULTS

A total of nine studies were included, representing 3161 breasts. There was no significant difference in postoperative outcomes, such as seroma formation (p = 0.51), hematomas (p = 0.20), infections (p = 0.21), wound dehiscence (p = 0.09), reoperations (p = 0.70), implant loss (p = 0.27), or skin necrosis (p = 0.21). Only two of the studies included evaluated patient-reported outcomes between the use and non-use of ADM in implant-based breast reconstruction using BREAST-Q questionnaire, as well as self-reported pain. There was no reported significant difference in BREAST-Q or pain scores.

CONCLUSIONS

This meta-analysis shows comparable short- and long-term outcomes between ADM and non-ADM breast reconstruction, suggesting that the use of ADM may not be necessary in all cases given their additional cost. However, there is a paucity of data for patient-reported outcomes, and further research is required to determine whether ADM use affects patient-reported outcomes.

Do we need acellular dermal matrix in prepectoral breast reconstruction? A systematic review and meta-analysis

Acellular dermal matrices (ADMs) are commonly used in prepectoral breast reconstruction. However, ADM is associated with high cost and potentially infection and seroma. Comparative studies on prepectoral reconstruction with and without ADM are limited to small, single-institution series. The purpose of this study was to perform a meta-analysis of prepectoral reconstruction with and without ADM. A systematic literature review was performed to identify studies comparing prepectoral reconstruction with and without ADM using PubMed, EMBASE, and Cochrane databases. Pooled rates of patient demographics and outcomes were analyzed. Meta-analytic effect size estimates were calculated for reconstructive complications in studies comparing reconstruction with and without ADM. In total, 515 reconstructions from four studies were included. Most cases were nipple-sparing mastectomies and utilized tissue-expander reconstructions. Meta-analysis demonstrated no significant difference in the rate of complications between cohorts with and without ADM. Short-term complications included reconstructive failure (1.2% in ADM cohort and 2.8% in no-ADM), seroma (1.2% and 8.3%, respectively), hematoma (1.2% and 2.1%), infection (4.7% and 4.2%), and mastectomy flap ischemia and/or necrosis (2.4% and 5.2%). Long-term complications included rippling (3.3% in ADM and 5.1% in no-ADM cohorts) and capsular contracture (6.8% and 3.4%, respectively). This meta-analysis demonstrated no difference in the rate of complications between cases with and without ADM. However, the outcomes data from no-ADM reconstruction mostly reflect robust mastectomy flaps. Surgeon discretion as informed by specific clinical scenarios should guide decisions regarding the use of ADM in prepectoral breast reconstruction.

Rise of Acellular Dermal Matrix: Cost Consciousness, Industry Payment, and Publication Productivity

BACKGROUND

Despite high cost and lack of FDA approval for breast surgery, acellular dermal matrix (ADM) has become commonplace in reconstructive surgery and has been the focus of more than 500 plastic surgery publications since its wide adoption. We hypothesized that ADM-related academic output would correlate with public interest and industry funding.

STUDY DESIGN

All PubMed-indexed studies focusing on ADM in 11 plastic surgery journals were included (n = 535). Data on industry funding to the 17 most productive authors were extracted from the Open Payments Database. Google Trends in "breast surgery cost" and related terms were queried. Relationships among publication quantity, author industry funding, and public interest were analyzed by Pearson's correlation and linear regression.

RESULTS

The most published authors produced 8 qualifying publications on average (range 5 to 17), with 80% focused on breast surgery. These individuals grossed a total of $19 million industry dollars overall with $17 million (89%) in nonconsulting compensation from ADM-producing companies (NC-ADM). Individual total compensation and NC-ADM compensation, by quartile, were $194,000/$320,000/$1.25 million and $17,000/$210,000/$1.1 million, respectively. These variables showed strong correlation with individual publication rate with a linear regression coefficient of $110K in NC-ADM per publication (p < 0.01). Authors disclosed funding in a mean ± SD of 65 ± 26% of their work with strong correlation between disclosure and NC-ADM (p < 0.01). Google "breast surgery cost" search volume has grown rapidly in significant correlation with ADM publications (p = 0.02).

CONCLUSIONS

This study demonstrates significant correlation between ADM-related publication, industry funding, funding disclosure, and public interest. Education in the potential for such relationships and the importance of objectivity in plastic surgery warrants discussion.

ADMs and synthetic meshes improve implant-based breast reconstruction aesthetics, but at what cost?

Acellular dermal matrices (ADMs) have shown promise for use in reconstructive breast surgery as they improve aesthetic outcomes and decrease capsular contracture rates. However, concerns about their use remain because of the higher cost and complication profile. We report a single institution's implant-based-reconstruction (IBR) experience between 2007 and 2021, including cases performed by 51 plastic surgeons. For each stage of IBR, data on age, comorbidities, type of mesh used, and acute complications were collected. Of 1379 patients who underwent subpectoral IBR, 937 received an ADM or synthetic mesh as part of their reconstruction. 256 patients out of 264 treated with prepectoral IBR received an ADM or mesh. Infection and wound dehiscence rates were highest for patients who underwent prepectoral IBR with ADM. Both subpectoral and prepectoral IBR with ADM were associated with higher rates of infection and wound complications compared to without ADM or mesh, but only the difference among the subpectoral cohort reached statistical significance. Prepectoral IBR with ADM or mesh had the lowest rates of capsular contracture and aesthetic reoperations. Although the use of Vicryl® mesh in subpectoral IBR was associated with a higher risk of capsular contracture and skin flap necrosis compared to reconstruction with ADMs (10.53% versus 3.29%; p < 0.05), Vicryl® was associated with fewer aesthetic revisions. Our study demonstrated that prepectoral IBR with ADM or mesh resulted in the fewest aesthetic reoperations and the lowest rates of capsular contracture. Infection and wound dehiscence rates were notably higher for patients who had reconstruction with ADM.

Early Clinical Outcomes of Polydioxanone Mesh for Prepectoral Prosthetic Breast Reconstruction

Many biologic matrices and synthetic meshes are available as adjuncts for prosthetic and autologous breast reconstructions to help control implant position and to reinforce abdominal flap donor sites. Absorbable synthetic meshes may have advantages over biologic matrices and permanent meshes, such as lower cost and better long-term biocompatibility. We present a prospective case series of patients undergoing two-stage, prepectoral breast reconstruction with polydioxanone (PDO) mesh.

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.

Human Acellular Dermal Matrix (Epiflex®) in Immediate Implant-Based Breast Reconstruction after Skin- and Nipple-Sparing Mastectomy and Treatment of Capsular Fibrosis: Results of a Multicenter, Prospective, Observational NOGGO-AWOGyn Study

Background

Over the last decades, the number of acellular dermal matrix (ADM)-assisted implant-based breast reconstructions (IBBR) has substantially increased. However, there is still a lack of prospective data on complication rates.

Methods

We performed a non-interventional, multicenter, prospective cohort study to evaluate complication rates of a human ADM in patients undergoing an IBBR after skin- and nipple-sparing mastectomies. Patients with primary reconstruction (cohort A) and patients undergoing a secondary reconstruction after capsular fibrosis (cohort B) using the human ADM Epiflex® (DIZG gGmbH, Berlin, Germany) were enrolled in this study. Patients were followed-up for 12 months after surgery.

Results

Eighty-four eligible patients were included in this study of whom 28 women underwent a bilateral breast reconstruction, leading to 112 human ADM-assisted reconstructions in total (cohort A: 73, cohort B: 39). In 33.0% of the reconstructed breasts at least one of the complications of primary interest occurred, including implant loss 7.1%, seroma 15.2%; infection 5.4%, rash 8.0%, and Baker grade III/IV capsular fibrosis 2.7%, with no statistically significant differences between the cohorts. Previous radiation therapy was significantly associated with occurrence of any postoperative complication (OR 20.41; p value 0.027).

Conclusion

The rates of most complications were comparable to the rates reported for other ADMs with relatively low rates of capsular fibrosis and infections. The rate of seroma was increased in our study. Prior radiation therapy increased the risk of any postoperative complications. Therefore, the use of ADM in these patients should be considered carefully.

Acellular Dermal Matrix-Associated Complications in Implant-Based Breast Reconstruction: A Multicenter, Prospective, Randomized Controlled Clinical Trial Comparing Two Human Tissues

BACKGROUND

Implant-based breast reconstruction accounts for the vast majority of breast reconstruction procedures and is commonly performed with human acellular dermal matrix. There is no consensus as to the optimal human acellular dermal matrix preparation, and high-quality evidence concerning comparative effectiveness is lacking. This study is the first prospective, multicenter, randomized controlled clinical trial to compare human acellular dermal matrix-related complications of the two most commonly used human acellular dermal matrices in implant-based breast reconstruction. The authors hypothesize that there will be no difference in infection, seroma, and reconstructive failure between FlexHD Pliable and AlloDerm RTU.

METHODS

The authors conducted a Level 1 prospective, randomized, controlled, multicenter clinical trial to assess complications associated with the use of two human acellular dermal matrices in immediate postmastectomy implant-based breast reconstruction across seven clinical sites. Group A patients received FlexHD Pliable (113 patients with 187 breast reconstructions), and group B patients received AlloDerm RTU (117 patients with 197 breast reconstructions).

RESULTS

There was no significant difference with respect to patient demographics, indications, comorbidities, and reconstruction approach between groups. Mean follow-up time was 10.7 ± 3.2 months. There was no statistical difference in the overall matrix-related complications between groups A and B (4.3 percent versus 7.1 percent, p = 0.233). Obesity (OR, 1.14; 95 percent CI, 1.05 to 1.24; p = 0.001) and prepectoral placement of matrix (OR, 4.53; 95 percent CI, 1.82 to 11.3; p = 0.001) were independently associated with greater risks of overall matrix-related complications.

CONCLUSION

This work supports the use of human acellular dermal matrices in implant-based breast reconstruction and demonstrates no significant difference in matrix-related complication rates between FlexHD Pliable and AlloDerm RTU.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, I.

Do We Need Support in Prepectoral Breast Reconstruction? Comparing Outcomes with and without ADM

Background:

The majority of two-stage prepectoral breast reconstruction has been described utilizing acellular dermal matrix (ADM). Although reports of prepectoral breast reconstruction without ADM exist, there is a paucity of comparative studies.

Methods:

A single-institution retrospective review was performed of consecutive patients undergoing immediate prepectoral two-stage breast reconstruction with tissue expanders from 2017 to 2019. Short-term reconstructive and aesthetic complications were compared between cases that utilized ADM for support and those that did not.

Results:

In total, 76 cases (51 patients) were identified, of which 35 cases utilized ADM and 41 did not. Risk factors and demographics were similar between the two cohorts with the exception of body mass index, which was higher in the ADM cohort (29.3 versus 25.4, P = 0.011). Average follow-up length was also longer in patients who received ADM (20.3 versus 12.3 months, P < 0.001). Intraoperative expander fill was higher in patients who did not receive ADM (296.8 cm³ versus 151.4 cm³, P < 0.001) though final implant size was comparable in both cohorts (P = 0.584). There was no significant difference in the rate of any complication between the ADM and no ADM cohorts (25.7% versus 17.1%, respectively P = 0.357), including major mastectomy flap necrosis (P = 0.245), major infection (P = 1.000), seroma (P = 0.620), expander explantation (P = 1.000), capsular contracture (P = 1.000), implant dystopia (P = 1.000), and rippling (P = 0.362).

Conclusions:

Immediate two-stage prepectoral breast reconstruction with tissue expanders has comparable rates of short-term complications with or without ADM support. Safety of prepectoral expander placement without ADM may warrant more selective ADM use in these cases.

Patient-Reported Outcomes and Aesthetic Results after Immediate Breast Reconstruction Using Human Acellular Dermal Matrices: Results of a Multicenter, Prospective, Observational NOGGO-AWOGyn Study

BACKGROUND

With the increased use of acellular dermal matrices (ADMs) in implant-based breast reconstructions (IBBRs), the evaluation of patient-reported outcomes becomes more important.

METHODS

Patients who underwent an immediate human ADM-assisted, submuscular IBBR were included in this noninterventional, multicenter, prospective cohort study. Patients with primary reconstruction (cohort A) and patients with a revision surgery after capsular fibrosis (cohort B) were followed up for 12 months after surgery. Quality of life (EORTC BR-23) and patient and surgeon satisfaction scores (1 ["very satisfied"] to 6 ["not satisfied"]) with the outcome and the aesthetic result evaluated by 2 independent, external experts were assessed.

RESULTS

Eighty-four patients were enrolled in the study. The mean patient satisfaction score was 2.1 ± 0.8, with higher satisfaction in cohort B (p = 0.041). The score did not change significantly during the follow-up (p = 0.479). The mean satisfaction score of the surgeons was 2.0 ± 0.7; it was also higher in cohort B (p = 0.016) and showed no changes over time (p = 0.473). The mean aesthetic result was 2.2 ± 0.7. 92.9% of the patients completed at least 1 quality of life questionnaire. Body image and sexual functioning increased during follow-up. One year after surgery, the mean scores were 77.2 ± 22.5 and 44.7 ± 27.3, respectively.

CONCLUSION

The level of satisfaction among patients and surgeons and the score of the aesthetic result were constantly high among patients after ADM-assisted IBBR. Higher satisfaction scores could be observed after revision surgery caused by capsular fibrosis (cohort B) compared to primary reconstruction (cohort A). Quality of life increased during the first year after surgery.

A comparative study of pre- or subpectoral expander position with the fenestrated Acellular dermal matrix anterior coverage, on drainage volume and Seroma Formation after Non-Nipple-Sparing Mastectomy

BACKGROUND

It has been reported that the use of the acellular dermal matrix (ADM) in expander-based breast reconstruction is related to an increase in seroma-related complications. The aim of this study is to compare the actual drainage volume, time to drain removal, and seroma formation rate in patients with prepectoral expander placement with anterior coverage of a fenestrated ADM to those patients with partial subpectoral expander placement with inferior coverage of a fenestrated ADM.

METHODS

This is a single-surgeon retrospective review of patients who underwent prepectoral expander-based breast reconstruction following non-nipple-sparing mastectomy. Patient demographics, operative data, and complications were analyzed and multivariate linear regression analyses were conducted to evaluate the significance of factors that influences total volume of fluid formation.

RESULTS

A total of 89 breasts from 87 patients were included in the study. Twenty-seven breasts had prepectoral expander reconstruction and 62 breasts had partial subpectoral expander reconstruction. Mean total volumes of fluid formation (total drainage volume + additional aspirated volume) were not significantly different (p = 0.190) in the two groups. In the subpectoral group only, high body mass index (BMI) was correlated with the total volume of fluid formation among the independent factors. (p = 0.017) CONCLUSIONS: Although total drainage volume was not significantly different between prepectoral and subpectoral groups, prepectoral positioning of the expander can be a protective factor against seroma formation in high BMI patients. Further definitive studies with larger patient numbers are warranted to corroborate these data and draw definitive conclusions.

The Use of Absorbable Mesh in Implant-Based Breast Reconstruction: A 7-Year Review

Breast reconstruction is most frequently performed using implants or expanders. Adjunctive materials such as acellular dermal matrix and synthetic meshes are used to support the implant or expander. A paucity of large studies exist on the use of synthetic mesh for breast reconstruction.

Breast Implants for Mammaplasty: An Umbrella Review of Meta-analyses of Multiple Complications

BACKGROUND

The association of breast implants and complications after mammaplasty has been extensively researched. The aim of this study is to summarize all available results in meta-analysis investigating the association between implants and the incidence of various complications.

METHODS

An umbrella review for breast implants and associated complications was performed by searching related reviews from electronic databases including Pubmed, Ovid and CINAHL. We collected and reviewed evidence across meta-analyses of observational and interventional studies of implants and any health outcome. The quality of the reviews was assessed using the AMSTAR tool (A measurement tool to assess systematic reviews).

RESULTS

The research included 92 meta-analyses of 609 studies concerning various areas. Capsular contracture was the most investigated outcome. Radiotherapy, human acellular dermal matrix application, direct-to-implant reconstruction, smooth implant, silicone-filled implant and periareolar incision were significantly associated with higher rates of some of the complications.

CONCLUSIONS

This umbrella review provides surgeons with summarized evidence of the association between the complications and implant-related factors in mammaplasty surgery to help surgeons make informed choices in the future.

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 .

The modified serratus anterior fascia flap improves satisfaction and long-term results in immediate implant-based breast reconstruction: A retrospective study

After immediate implant-based breast reconstruction (IIBR) following skin-sparing mastectomy, postoperative complications such as implant exposure or badly defined mammary folds can occur. Acellular dermal matrix can provide good esthetic outcomes but remain expensive. This study evaluates a new technique of one-stage IIBR by using a modified serratus anterior fascia flap (MSFF group), providing lower implant coverage, as compared to the classical submuscular technique. In this retrospective study, we included all patients who underwent IIBR using either the MSFF technique or the classic technique between November 2012 and February 2015. We collected data regarding demographics, perioperative factors, postoperative complications, patient satisfaction (Breast-Q score), and esthetic outcomes. One hundred twenty-three patients who underwent IIBR, of which 61 breasts (59 patients) using the MSFF and 67 breasts (64 patients) the classical technique, were included. The size of the implants used were significantly higher in the MSFF group (p = 0.036). There were no statistically significant differences between the two groups with regard to the immediate complications rate. After a mean follow-up of 43.9 months, we observed more capsular contractures in the classic group (p < 0.001). In the classic group, patients required more revision surgeries (p = 0.008), more implant changes (p < 0.001), and higher volume of additional lipofilling (p < 0.001). According to the Breast Q scores, patients' satisfaction was better in the MSFF group regarding their breasts (p = 0.001) and the outcomes (p = 0.009). The MSFF is a simple, safe, effective, and inexpensive autologous technique for IIBR, which improves implant coverage with a vascularized flap and provides satisfying outcomes as compared to classic IIBR, with less complications.

Acellular Dermal Matrix Sterility: Does It Affect Microbial and Clinical Outcomes Following Implantation?

The use of acellular dermal matrices (ADMs) in breast reconstruction is a controversial topic. Recent literature has investigated the effects of ADM sterilization on infectious complications, although with varying conclusions. Previous work by our group showed no difference between aseptic and sterilized products immediately out of the package. In this study, we investigate the microbiologic profiles of these agents after implantation.

Recent development and biomedical applications of decellularized extracellular matrix biomaterials

Decellularized matrix (dECM) is isolated extracellular matrix of tissues from its original inhabiting cells, which has emerged as a promising natural biomaterial for tissue engineering, aiming at support, replacement or regeneration of damaged tissues. The dECM can be easily obtained from tissues/organs of various species by adequate decellularization methods, and mimics the structure and composition of the native extracellular matrix, providing a favorable cellular environment. In this review, we summarize the recent developments in the preparation of dECM materials, including decellularization, crosslinking and sterilization. Also, we cover the advances in the utilization of dECM biomaterials in regeneration medicine in pre-clinic and clinical trials. Moreover, we highlight those emerging medical benefits of dECM beyond tissue engineering, such as cell transplantation, in vitro/in vivo model and therapeutic cues delivery. With the advances in the preparation and broader application, the dECM biomaterials could become the gold scaffold and pharmaceutical excipients in medical sciences.

Comparison of prepectoral and subpectoral breast reconstruction after mastectomies: A systematic review and meta analysis

BACKGROUND

The safety of prepectoral breast reconstruction (PBR) after mastectomies as compared to subpectoral breast reconstruction (SBR) were unclear, so we conducted a systematic review to analyze their differences.

METHODS

PubMed, EMBASE, the Cochrane Library, and Web of Science databases were searched to retrieve studies that compared PBR with SBR after mastectomies. The outcomes were complications, oncological safety, patient-reported outcomes and postoperative pain. Revman software version 5.30 and stata vesion 12 was used to conduct meta-analysis where possible.

RESULTS

16 comparative studies (12 articles and four abstracts) were included. The meta analysis showed no statistical differences in overall complications, implant loss, seroma, nipple or skin flap necrosis, hematoma, reoperation, wound dehiscence, and wound-skin infection, rippling between PBR and SBR. PBR might be associated with fewer nipple or skin flap necrosis for those who received tissue expander placement, and fewer capsular contracture rates for those who received implant. PBR might be associated with better Breast Q scores and less postoperative pain without increasing the risk of local recurrence and metastatic disease.

CONCLUSION

Although available evidence is limited, PBR might be as safe as subpectoral approach. Future well designed multicenter randomized controlled trial that compare postmastectomy PBR with SBR is needed.