Significance of Infections in Implant Loss After Breast Reconstruction in the Course of Breast Cancer Treatment

Evaluation of pathogen distribution and antimicrobial resistance in breast plastic surgery infection

BACKGROUND

The demand for mammaplasty has increased in recent years, and infection remains one of the common and serious post-operative complications. In this study, we analyzed the pathogen distribution and antibiotic susceptibility of breast plastic surgery infections, and compared the differences in pathogenic species between surgical procedures.

METHODS

The number of each species was counted in the microbial samples of breast plastic surgery infections in Plastic Surgery Hospital of Chinese Academy of Medical Sciences from January 2011 to December 2021. The in vitro antibiotic sensitivity testing data were analyzed using WHONET 5.6 software. The surgical techniques, the period of infection, and other details were gathered in accordance with the clinical data.

RESULTS

There were a total of 42 cases included, and 43 different types of pathogenic bacteria, mostly gram-positive bacteria, were found. CoNS (13/43) and Staphylococcus aureus (22/43) made up the majority. The most prevalent of the five Gram-negative bacteria was Pseudomonas aeruginosa. Results of drug sensitivity tests indicate that S. aureus is highly sensitive to vancomycin, cotrimoxazole, and linezolid, whereas CoNS is highly sensitive to vancomycin, linezolid, and chloramphenicol. Both of these bacteria show high resistance to erythromycin and penicillin. Breast augmentation, breast reconstruction, and breast reduction surgery were the most frequently associated breast surgery procedures in this study with infections, with the highest number of infections occurring following breast augmentation with fat grafting, breast reduction surgery, and breast reconstruction with autologous tissue. Various breast plastic surgery procedures have different common pathogens of infection, but the most prevalent are CoNS and S. aureus. Additionally, the majority of the infections in this study were in the early stages.

CONCLUSIONS

Gram-positive bacteria were the predominant cause of breast plastic surgery infections, and the types of infection strains, the period of infection onset, and the antibiotic susceptibility of prevalent strains varied between breast plastic procedures.

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.

The Impact of Nasal Staphylococcus aureus Carriage on Surgical-Site Infections after Immediate Breast Reconstruction: Risk Factors and Biofilm Formation Potential

BACKGROUND Despite the benefits of implant-based breast reconstruction in patients with breast cancer, the procedure can be complicated by surgical site infections (SSI). This study aimed to evaluate the association between nasal carriage of Staphylococcus aureus strains and the incidence of SSI among patients who underwent reconstructive procedures. We also assessed the ability of colonizing S. aureus strains to form biofilm. MATERIAL AND METHODS Medical data from 124 patients with 132 post-mastectomy breast reconstructions performed at the Oncology Center in Bydgoszcz, Poland, between June 2020 and August 2021 were analyzed. A 90-day incidence of SSI was found in 7/132 reconstructions (5.3%). The study group included 132 reconstructions, and was divided into those with infection (n=7) and without infection (n=125). Between-group differences were assessed using the t test for continuous variables and chi-square test for categorical variables. Biofilm formation among 32 S. aureus strains was determined by using quantitative and qualitative assays. RESULTS There were no significant differences in relation to the patients' S. aureus colonization status. Infections occurred both in patients colonized and not colonized with S. aureus. S. aureus nasal carriage did not affect the rate of SSI at 90 days after surgery. About 97.0% of the strains had a strong capacity for biofilm formation. CONCLUSIONS There was no association between nasal carriage of strains of S. aureus and the incidence of SSI. However, further investigations on a larger group of patients and longer observation time are needed to investigate this potential risk factor in detail.

Effectiveness of Single vs Multiple Doses of Prophylactic Intravenous Antibiotics in Implant-Based Breast Reconstruction: A Randomized Clinical Trial

Importance

Multiple-dose antibiotic prophylaxis is widely used to prevent infection after implant-based breast reconstruction despite the lack of high-level evidence regarding its clinical benefit.

Objective

To determine whether multiple-dose antibiotic prophylaxis is superior to single-dose antibiotic prophylaxis in preventing surgical site infection (SSI) after implant-based breast reconstruction.

Design, Setting, and Participants

This prospective, multicenter, randomized clinical superiority trial was conducted at 7 hospitals (8 departments) in Sweden from April 25, 2013, to October 31, 2018. Eligible participants were women aged 18 years or older who were planned to undergo immediate or delayed implant-based breast reconstruction. Follow-up time was 12 months. Data analysis was performed from May to October 2021.

Interventions

Multiple-dose intravenous antibiotic prophylaxis extending over 24 hours following surgery, compared with single-dose intravenous antibiotic. The first-choice drug was cloxacillin (2 g per dose). Clindamycin was used (600 mg per dose) for patients with penicillin allergy.

Main Outcomes and Measures

The primary outcome was SSI leading to surgical removal of the implant within 6 months after surgery. Secondary outcomes were the rate of SSIs necessitating readmission and administration of intravenous antibiotics, and clinically suspected SSIs not necessitating readmission but oral antibiotics.

Results

A total of 711 women were assessed for eligibility, and 698 were randomized (345 to single-dose and 353 to multiple-dose antibiotics). The median (range) age was 47 (19-78) years for those in the multiple-dose group and 46 (25-76) years for those in the single-dose group. The median (range) body mass index was 23 (18-38) for the single-dose group and 23 (17-37) for the multiple-dose group. Within 6 months of follow-up, 30 patients (4.3%) had their implant removed because of SSI. Readmission for intravenous antibiotics because of SSI occurred in 47 patients (7.0%), and 190 women (27.7%) received oral antibiotics because of clinically suspected SSI. There was no significant difference between the randomization groups for the primary outcome implant removal (odds ratio [OR], 1.26; 95% CI, 0.69-2.65; P = .53), or for the secondary outcomes readmission for intravenous antibiotics (OR, 1.18; 95% CI, 0.65-2.15; P = .58) and prescription of oral antibiotics (OR, 0.72; 95% CI, 0.51-1.02; P = .07). Adverse events associated with antibiotic treatment were more common in the multiple-dose group than in the single-dose group (16.4% [58 patients] vs 10.7% [37 patients]; OR, 1.64; 95% CI, 1.05-2.55; P = .03).

Conclusions and Relevance

The findings of this randomized clinical trial suggest that multiple-dose antibiotic prophylaxis is not superior to a single-dose regimen in preventing SSI and implant removal after implant-based breast reconstruction but comes with a higher risk of adverse events associated with antibiotic treatment.

Trial Registration

EudraCT 2012-004878-26.

Pseudomonas aeruginosa Infections in Cancer Patients

Pseudomonas aeruginosa (P. aeruginosa) is one of the most frequent opportunistic microorganisms causing infections in oncological patients, especially those with neutropenia. Through its ability to adapt to difficult environmental conditions and high intrinsic resistance to antibiotics, it successfully adapts and survives in the hospital environment, causing sporadic infections and outbreaks. It produces a variety of virulence factors that damage host cells, evade host immune responses, and permit colonization and infections of hospitalized patients, who usually develop blood stream, respiratory, urinary tract and skin infections. The wide intrinsic and the increasing acquired resistance of P. aeruginosa to antibiotics make the treatment of infections caused by this microorganism a growing challenge. Although novel antibiotics expand the arsenal of antipseudomonal drugs, they do not show activity against all strains, e.g., MBL (metalo-β-lactamase) producers. Moreover, resistance to novel antibiotics has already emerged. Consequently, preventive methods such as limiting the transmission of resistant strains, active surveillance screening for MDR (multidrug-resistant) strains colonization, microbiological diagnostics, antimicrobial stewardship and antibiotic prophylaxis are of particular importance in cancer patients. Unfortunately, surveillance screening in the case of P. aeruginosa is not highly effective, and a fluoroquinolone prophylaxis in the era of increasing resistance to antibiotics is controversial.

Preoperative Octenidine Application in Breast Reconstruction Surgery

BACKGROUND/AIM

Postoperative infection in implant-based reconstructive breast surgery is a common problem. The preoperative application of a disinfecting washing agent may reduce postoperative infection rates. This retrospective analysis aimed to evaluate whether preoperative Octenisan^® application yields a reduction in postoperative complications or infection rates in breast reconstructive surgery.

PATIENTS AND METHODS

Between 2016 and 2019, 127 women received implant-based breast reconstruction at the municipal hospital of Cologne, Holweide, Germany. A total of 197 treatments were performed. After giving consent, patients were asked to use Octenisan^® wash lotion for five days before breast reconstructive surgery. All patients were asked by a simple questionnaire whether they performed showering and washing according to the proposed protocol. In 96 cases patients did adhere to the protocol. In 101 cases they did not. Patient cohorts were then divided into patients who had applied Octenisan^® wash lotion and patients who had not. Endpoints were defined as minor complications with no implant loss and major complications with consecutive implant loss.

RESULTS

Patient adherence to the application regimen was 48.7%. Overall minor complications occurred in 34.4% with preoperative Octenidine usage and 36.6% without preoperative Octenidine usage. Major complications happened in 7% with preoperative Octenidine and 5% without Octenidine. Overall, there was no significant difference concerning minor or major complication rates.

CONCLUSION

Preoperative washing protocols involving the Octenisan^® wash lotion is relatively cheap and easy to follow. There is evidence that washing protocols result in a reduction of S. aureus infections leading to a better perioperative outcome. Octenisan^® is safe to use in implant-based breast reconstructive surgery and is not associated with higher risks for patients. Our study did not yield any significant reduction in perioperative and postoperative complication and infection rates. This is attributed to a relatively low study population. Wash lotion compliance was only 48.7%. Proper patient education is crucial. With those preliminary data, it is now possible to design a larger analysis since patient adherence to washing protocol with Octenisan^® wash lotion has been established.

Tumor-related Microbiome in the Breast Microenvironment and Breast Cancer

Despite the significant progress in diagnosis and treatment over the past years in the understanding of breast cancer pathophysiology, it remains one of the leading causes of mortality worldwide among females. Novel technologies are needed to improve better diagnostic and therapeutic approaches, and to better understand the role of tumor-environment microbiome players involved in the progression of this disease. The gut environment is enriched with over 100 trillion microorganisms, which participate in metabolic diseases, obesity, and inflammation, and influence the response to therapy. In addition to the direct metabolic effects of the gut microbiome, accumulating evidence has revealed that a microbiome also exists in the breast and in breast cancer tissue. This microbiome enriched in the breast environment and the tumor microenvironment may modulate effects potentially associated with carcinogenesis and therapeutic interventions in breast tissue, which to date have not been properly acknowledged. Herein, we review the most recent works associated with the population dynamics of breast microbes and explore the significance of the microbiome on diagnosis, tumor development, response to chemotherapy, endocrine therapy, and immunotherapy. To overcome the low reproducibility of evaluations of tumor-related microbiome, sequencing technical escalation and machine deep learning algorithms may be valid for standardization of assessment for breast-related microbiome and their applications as powerful biomarkers for prognosis and predictive response in the future.

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

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