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OBJECTIVE: To implement the BREASTChoice decision tool into the electronic health record and evaluate its effectiveness. BACKGROUND: BREASTChoice , is a multilevel decision tool that: 1) educates patients about breast reconstruction; 2) estimates personalized risk of complications; 3) clarifies patient preferences; and 4) informs clinicians about patients' risk and preferences. METHODS: A multisite randomized controlled trial enrolled adult women with stage 0-III breast malignancy undergoing mastectomy. Participants were randomized to BREASTChoice or a control website. A survey assessed knowledge, preferences, decisional conflict, shared decision-making, preferred treatment, and usability. We conducted intent-to-treat (ITT), per-protocol (PP) analyses (those randomized to BREASTChoice who accessed the tool), and stratified analyses. RESULTS: 23/25 eligible clinicians enrolled. 369/761 (48%) contacted patients enrolled and were randomized. Patients' average age was 51 years; 15% were older than 65. BREASTChoice participants had higher knowledge than control participants (ITT: mean 70.6 vs. 67.4, P =0.08; PP: mean 71.4 vs. 67.4, P =0.03), especially when stratified by site (ITT: P =0.04, PP: P =0.01), age (ITT: P =0.04, PP: P =0.02), and race (ITT: P =0.04, PP: P =0.01). BREASTChoice did not improve decisional conflict, match between preferences and treatment, or shared decision-making. In PP analyses, fewer high-risk patients using BREASTChoice chose reconstruction. BREASTChoice had high usability. CONCLUSIONS: BREASTChoice is a novel decision tool incorporating risk prediction, patient education, and clinician engagement. Patients using BREASTChoice had higher knowledge; older adults and those from racially minoritized backgrounds especially benefitted. There was no impact on other decision outcomes. Future studies should overcome implementation barriers and specifically examine decision outcomes among high-risk patients.
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Implanted medical devices are widely used across various medical specialties for numerous applications, ranging from cardiovascular supports to orthopedic prostheses and cosmetic enhancements. However, recent observations have raised concerns about the potential of these implants to induce malignancies in the tissues surrounding them. There have been several case reports documenting the occurrence of cancers adjacent to these devices, prompting a closer examination of their safety. This review delves into the epidemiology, clinical presentations, pathological findings, and hypothesized mechanisms of carcinogenesis related to implanted devices. It also explores how the surgical domain and the intrinsic properties and biocompatibility of the implants might influence the development of these rare but serious malignancies. Understanding these associations is crucial for assessing the risks associated with the use of medical implants, and for developing strategies to mitigate potential adverse outcomes.
Subject(s)
Biocompatible Materials , Neoplasms , Prostheses and Implants , Humans , Biocompatible Materials/adverse effects , Prostheses and Implants/adverse effects , Neoplasms/etiology , AnimalsABSTRACT
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.
Subject(s)
Breast Implantation , Breast Implants , Breast Neoplasms , Mastectomy , Patient Reported Outcome Measures , Postoperative Complications , Tissue Expansion Devices , Tissue Expansion , Humans , Female , Prospective Studies , Middle Aged , Tissue Expansion Devices/adverse effects , Adult , Breast Implantation/methods , Breast Implantation/instrumentation , Breast Implantation/adverse effects , Mastectomy/adverse effects , Postoperative Complications/etiology , Postoperative Complications/epidemiology , Breast Neoplasms/surgery , Breast Implants/adverse effects , Tissue Expansion/instrumentation , Tissue Expansion/adverse effects , Tissue Expansion/methods , Treatment Outcome , Aged , Mammaplasty/methods , Mammaplasty/adverse effects , Time Factors , Patient SatisfactionABSTRACT
BACKGROUND: Breast implants are the most commonly used medical devices in plastic surgery, and capsular contracture (CC) is one of the most common complications. However, our assessment of CC is based largely on Baker grade, which is problematically subjective and affords only four possible values. METHODS: The authors performed a systematic review concluding in September of 2021 in compliance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. It identified 19 articles that propose approaches to measuring CC. RESULTS: In addition to Baker grade, the authors identified several modalities reported to measure CC. These included magnetic resonance imaging, ultrasonography, sonoelastography, mammacompliance measuring devices, applanation tonometry, histologic evaluation, and serology. Capsule thickness and other measures of CC inconsistently correlated with Baker grade, whereas the presence of synovial metaplasia was consistently associated with Baker grade I and II, but not III and IV capsules. CONCLUSIONS: There remains no particular method to reliably and specifically measure the contracture of capsules that form around breast implants. As such, we would recommend that research investigators use more than one modality to measure CC. Other variables that can impact breast implant stiffness and associated discomfort beyond CC need to be considered when evaluating patient outcomes. Given the value placed on CC outcomes in assessing breast implant safety, and the prevalence of breast implants overall, the need for a more reliable approach to measuring this outcome persists.
Subject(s)
Breast Implantation , Breast Implants , Contracture , Humans , Consensus , Breast Implants/adverse effects , Breast Implantation/adverse effects , Breast Implantation/methods , Breast/pathology , Contracture/diagnosis , Contracture/etiology , Contracture/pathology , Implant Capsular Contracture/diagnosis , Implant Capsular Contracture/etiologyABSTRACT
BACKGROUND: Several acellular dermal matrices (ADMs) are utilized for soft tissue support in prosthetic breast reconstruction. Little high-level evidence supports the use of one ADM over another. Therefore, we sought to compare Cortiva 1mm Allograft Dermis to AlloDerm RTU, the most studied ADM in the literature. METHODS: A single-blinded randomized controlled trial comparing Cortiva to AlloDerm in prepectoral and subpectoral immediate prosthetic breast reconstruction was performed at two academic hospitals from March 2017 to December 2021. Reconstructions were direct-to-implant (DTI) or tissue expander (TE). Primary outcome was reconstructive failure, defined as TE explantation prior to planned further reconstruction, or explantation of DTI reconstructions before 3 months postoperatively. Secondary outcomes were additional complications, patient-reported outcomes (PROs), and cost. RESULTS: There were 302 patients included - 151 AlloDerm (280 breasts), 151 Cortiva (277 breasts). Reconstructions in both cohorts were majority TE (62% vs 38% DTI), smooth device (68% vs 32% textured), and prepectoral (80% vs 20% subpectoral). Reconstructive failure was no different between ADMs (AlloDerm 9.3% vs Cortiva 8.3%, p=0.68). There were no additional differences in any complications or PROs between ADMs. Seromas occurred in 7.6% of Cortiva but 12 % of AlloDerm cases, whose odds of seroma formation were two-fold (OR 1.93, 95% CI 1.01-3.67, p=0.047) higher. AlloDerm variable cost was 10-15% more than Cortiva, and there were no additional cost differences. CONCLUSION: When assessing safety, clinical performance, PROs, and cost, Cortiva is non-inferior to AlloDerm in immediate prosthetic breast reconstruction and may be cheaper with lower risk of seroma formation.
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LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Understand how bacteria negatively impact aesthetic and reconstructive breast implants. 2. Understand how bacteria infect breast implants. 3. Understand the evidence associated with common implant infection-prevention strategies, and their limitations. 4. Understand why implementation of bacteria-mitigation strategies such as antibiotic administration or "no-touch" techniques may not indefinitely prevent breast implant infection. SUMMARY: Bacterial infection of aesthetic and reconstructive breast implants is a common and expensive problem. Subacute infections or chronic capsular contractures leading to device explantation are the most commonly documented sequelae. Although bench and translational research underscores the complexities of implant-associated infection, high-quality studies with adequate power, control groups, and duration of follow-up are lacking. Common strategies to minimize infections use antibiotics-administered systemically, in the breast implant pocket, or by directly bathing the implant before insertion-to limit bacterial contamination. Limiting contact between the implant and skin or breast parenchyma represents an additional common strategy. The clinical prevention of breast implant infection is challenged by the clean-contaminated nature of breast parenchyma, and the variable behavior of not only specific bacterial species but also their strains. These factors impact bacterial virulence and antibiotic resistance.
Subject(s)
Breast Implantation , Breast Implants , Prosthesis-Related Infections , Humans , Breast Implants/adverse effects , Breast Implants/microbiology , Prosthesis-Related Infections/prevention & control , Prosthesis-Related Infections/microbiology , Breast Implantation/methods , Biofilms , Anti-Bacterial Agents/therapeutic use , BacteriaABSTRACT
Bacterial infection is the most common complication following staged post-mastectomy breast reconstruction initiated with a tissue expander (TE). To limit bacterial infection, antibiotic irrigation of the surgical site is commonly performed despite little high-quality data to support this practice. We performed a prospective randomized control trial to compare the impact of saline irrigation alone to a triple antibiotic irrigation regimen (1 g cefazolin, 80 mg gentamicin, and 50,000 units of bacitracin in 500 mL of saline) for breast implant surgery. The microbiome in breasts with cancer (n = 16) was compared to those without (n = 16), as all patients (n = 16) had unilateral cancers but bilateral mastectomies (n = 32). Biologic and prosthetic specimens procured both at the time of mastectomy and during TE removal months later were analyzed for longitudinal comparison. Outcomes included clinical infection, bacterial abundance, and relative microbiome composition. No patient in either group suffered a reconstructive failure or developed an infection. Triple antibiotic irrigation administered at the time of immediate TE reconstruction did not reduce bacterial abundance or impact microbial diversity relative to saline irrigation at the time of planned exchange. Implanted prosthetic material adopted the microbial composition of the surrounding host tissue. In cancer-naïve breasts, relative to saline, antibiotic irrigation increased bacterial abundance on periprosthetic capsules (P = 0.03) and acellular dermal matrices (P = 0.04) and altered the microbiota on both. These data show that, relative to saline only, the use of triple antibiotic irrigation in TE breast reconstruction does impact the bacterial abundance and diversity of certain biomaterials from cancer-naïve breasts. IMPORTANCE The lifetime risk of breast cancer is ~13% in women and is treated with a mastectomy in ~50% of cases. The majority are reconstructed, usually starting with a tissue expander to help restore the volume for a subsequent permanent breast implant or the women's own tissues. The biopsychosocial benefits of breast reconstruction, though, can be tempered by a high complication rate of at least 7% but over 30% in some women. Bacterial infection is the most common complication, and can lead to treatment delays, patient physical and emotional distress and escalating health care cost. To limit this risk, plastic surgeons have tried a variety of strategies to limit bacterial infection including irrigating the pocket created after removing the breast implant with antibiotic solutions, but good-quality data are scarce. Herein, we study the value of antibiotics in pocket irrigation using a robust randomized clinical trial design and molecular microbiology approaches.
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Breast implants, whether placed for reconstructive or cosmetic purposes, are rarely lifetime devices. Rupture, resulting from compromised implant shell integrity, and capsular contracture caused by constriction of the specialized scar tissue that normally forms around breast implants, have long been recognized, and remain the leading causes of implant failure. It is apparent, however, that women with breast implants may also experience delayed breast swelling due to a range of etiologic factors. While a majority of delayed seromas associated with breast implants have a benign etiology, this presentation cannot be ignored without an adequate workup as malignancies such as breast implant associated anaplastic large cell lymphoma (BIA-ALCL), breast implant associated diffuse large B-cell lymphoma (BIA-DLBCL), and breast implant associated squamous cell carcinoma (BIA-SCC) can have a similar clinical presentation. Since these malignancies occur with sufficient frequency, and with sometimes lethal consequences, their existence must be recognized, and an appropriate diagnostic approach implemented. A multidisciplinary team that involves a plastic surgeon, radiologist, pathologist, and, as required, surgical and medical oncologists can expedite judicious care. Herein we review and further characterize conditions that can lead to delayed swelling around breast implants.
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BACKGROUND: Coronavirus disease of 2019 (COVID-19) poses unique challenges for breast reconstruction. At the authors' institution, COVID-19 postoperative protocols mandated patients undergoing immediate prosthetic breast reconstruction transition from 23-hour postoperative observation to same-day discharge. The authors sought to compare complications and hospital costs between these groups. METHODS: A retrospective study of consecutive patients who underwent immediate prosthetic breast reconstruction from March of 2019 to April of 2021 at an academic hospital was performed. Before mid-March of 2020, patients were admitted postoperatively for observation; after mid-March of 2020, patients were discharged the same day. Postoperative complications at 48 hours, 30 days, and 90 days and hospital costs were compared. RESULTS: There were 238 patients included (119 outpatient and 119 observation). Across all time points, total complications, major complications, categorical complications (wound healing, seroma, hematoma, infection, implant exposure), and reconstructive failures were low and not statistically different between groups. There were no differences in 30-day hospital readmission/reoperation rates (7.6% outpatient versus 9.2% observation; P = 0.640). No patient or surgical factors predicted major complication or hematoma by 48 hours or infection by 90 days. At 90 days, radiation history ( P = 0.002) and smoking ( P < 0.001) were significant predictors of major complications. Average patient care costs outside of surgery-specific costs were significantly lower for outpatients ($1509 versus $4045; P < 0.001). CONCLUSIONS: Complications after immediate prosthetic breast reconstruction are low. Outpatient surgery is safe, harboring no increased risk of complications. Furthermore, outpatient care is more cost-effective. Therefore, surgeons should consider outpatient management of these patients to minimize COVID-19 exposure and reduce resource consumption, all while maintaining excellent surgical care. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.
Subject(s)
Breast Implants , Breast Neoplasms , COVID-19 , Mammaplasty , Humans , Female , Outpatients , Mastectomy/adverse effects , Retrospective Studies , Breast Neoplasms/etiology , COVID-19/epidemiology , COVID-19/complications , Mammaplasty/methods , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Breast Implants/adverse effectsSubject(s)
Breast Implants , Breast Neoplasms , Mammaplasty , Humans , Female , Mastectomy , Prostheses and Implants , Decision Making , Patient SatisfactionABSTRACT
Breast implant-associated infections (BIAIs) are the primary complication following placement of breast prostheses in breast cancer reconstruction. Given the prevalence of breast cancer, reconstructive failure due to infection results in significant patient distress and health care expenditures. Thus, effective BIAI prevention strategies are urgently needed. This study tests the efficacy of one infection prevention strategy: the use of a triple antibiotic pocket irrigant (TAPI) against Staphylococcus aureus, the most common cause of BIAIs. TAPI, which consists of 50,000 U bacitracin, 1 g cefazolin, and 80 mg gentamicin diluted in 500 mL of saline, is used to irrigate the breast implant pocket during surgery. We used in vitro and in vivo assays to test the efficacy of each antibiotic in TAPI, as well as TAPI at the concentration used during surgery. We found that planktonically grown S. aureus BIAI isolates displayed susceptibility to gentamicin, cefazolin, and TAPI. However, TAPI treatment enhanced biofilm formation of BIAI strains. Furthermore, we compared TAPI treatment of a S. aureus reference strain (JE2) to a BIAI isolate (117) in a mouse BIAI model. TAPI significantly reduced infection of JE2 at 1 and 7 days postinfection (dpi). In contrast, BIAI strain 117 displayed high bacterial burdens in tissues and implants, which persisted to 14 dpi despite TAPI treatment. Lastly, we demonstrated that TAPI was effective against Pseudomonas aeruginosa reference (PAO1) and BIAI strains in vitro and in vivo. Together, these data suggest that S. aureus BIAI strains employ unique mechanisms to resist antibiotic prophylaxis treatment and promote chronic infection. IMPORTANCE The incidence of breast implant associated infections (BIAIs) following reconstructive surgery postmastectomy remains high, despite the use of prophylactic antibiotic strategies. Thus, surgeons have begun using additional antibiotic-based prevention strategies, including triple antibiotic pocket irrigants (TAPIs). However, these strategies fail to reduce BIAI rates for these patients. To understand why these therapies fail, we assessed the antimicrobial resistance patterns of Staphylococcus aureus strains, the most common cause of BIAI, to the antibiotics in TAPI (bacitracin, cefazolin, and gentamicin). We found that while clinically relevant BIAI isolates were more susceptible to the individual antibiotics compared to a reference strain, TAPI was effective at killing all the strains in vitro. However, in a mouse model, the BIAI isolates displayed recalcitrance to TAPI, which contrasted with the reference strain, which was susceptible. These data suggest that strains causing BIAI may encode specific recalcitrance mechanisms not present within reference strains.
Subject(s)
Breast Implants , Staphylococcal Infections , Animals , Mice , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Staphylococcus aureus , Cefazolin/pharmacology , Cefazolin/therapeutic use , Breast Implants/microbiology , Bacitracin/pharmacology , Mastectomy , Staphylococcal Infections/drug therapy , Staphylococcal Infections/epidemiology , Staphylococcal Infections/microbiology , Polymyxin B/therapeutic use , Gentamicins/pharmacology , Gentamicins/therapeutic use , Microbial Sensitivity TestsABSTRACT
BACKGROUND: Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare malignancy originating from the periprosthetic capsule of a textured, most often macrotextured, breast implant. Identified in women whose indications for breast implants can be either aesthetic or reconstructive, the genomic underpinnings of this disease are only beginning to be elucidated. OBJECTIVES: The aim of this study was to evaluate the exomes, and in some cases the entire genome, of patients with BIA-ALCL. Specific attention was paid to copy number alterations, chromosomal translocations, and other genomic abnormalities overrepresented in patients with BIA-ALCL. METHODS: Whole-exome sequencing was performed on 6 patients, and whole-genome sequencing on 3 patients, with the Illumina NovaSeq 6000 sequencer. Data were analyzed with the Illumina DRAGEN Bio-IT Platform and the ChromoSeq pipeline. The Pathseq Genome Analysis Toolkit pipeline was used to detect the presence of microbial genomes in the sequenced samples. RESULTS: Two cases with STAT3 mutations and 2 cases with NRAS mutations were noted. A critically deleted 7-Mb region was identified at the 11q22.3 region of chromosome 11, and multiple nonrecurrent chromosomal rearrangements were identified by whole-genome sequencing. Recurrent gene-level rearrangements, however, were not identified. None of the samples showed evidence of potential microbial pathogens. CONCLUSIONS: Although no recurrent mutations were identified, this study identified mutations in genes not previously reported with BIA-ALCL or other forms of ALCL. Furthermore, not previously reported with BIA-ALCL, 11q22.3 deletions were consistent across whole-genome sequencing cases and present in some exomes.
Subject(s)
Breast Implantation , Breast Implants , Breast Neoplasms , Lymphoma, Large-Cell, Anaplastic , Humans , Female , Lymphoma, Large-Cell, Anaplastic/pathology , Exome , MutationABSTRACT
Patient decision aids can support shared decision making and improve decision quality. However, decision aids are not widely used in clinical practice due to multiple barriers. Integrating patient decision aids into the electronic health record (EHR) can increase their use by making them more clinically relevant, personalized, and actionable. In this article, we describe the procedures and considerations for integrating a patient decision aid into the EHR, based on the example of BREASTChoice, a decision aid for breast reconstruction after mastectomy. BREASTChoice's unique features include 1) personalized risk prediction using clinical data from the EHR, 2) clinician- and patient-facing components, and 3) an interactive format. Integrating a decision aid with patient- and clinician-facing components plus interactive sections presents unique deployment issues. Based on this experience, we outline 5 key implementation recommendations: 1) engage all relevant stakeholders, including patients, clinicians, and informatics experts; 2) explicitly and continually map all persons and processes; 3) actively seek out pertinent institutional policies and procedures; 4) plan for integration to take longer than development of a stand-alone decision aid or one with static components; and 5) transfer knowledge about the software programming from one institution to another but expect local and context-specific changes. Integration of patient decision aids into the EHR is feasible and scalable but requires preparation for specific challenges and a flexible mindset focused on implementation. Highlights: Integrating an interactive decision aid with patient- and clinician-facing components into the electronic health record could advance shared decision making but presents unique implementation challenges.We successfully integrated a decision aid for breast reconstruction after mastectomy called BREASTChoice into the electronic health record.Based on this experience, we offer these implementation recommendations: 1) engage relevant stakeholders, 2) explicitly and continually map persons and processes, 3) seek out institutional policies and procedures, 4) plan for it to take longer than for a stand-alone decision aid, and 5) transfer software programming from one site to another but expect local changes.
Subject(s)
Breast Neoplasms , Mammaplasty , Breast Neoplasms/surgery , Decision Making , Decision Making, Shared , Female , Humans , Mastectomy/adverse effectsABSTRACT
BACKGROUND: A greater proportion of patients with surgical risk factors are undergoing immediate breast reconstruction after mastectomy, resulting in the need for better risk prediction to inform decisions about the procedure. The objective of this study was to leverage clinical data to restructure a previously developed risk model to predict serious infectious and noninfectious wound complications after mastectomy alone and mastectomy plus immediate reconstruction for use during a surgical consultation. METHODS: The study established a cohort of women age 21 years or older treated with mastectomy from 1 July 2010 to 31 December 2015 using electronic health records from two hospitals. Serious infectious and non-infectious wound complications, defined as surgical-site infection, dehiscence, tissue necrosis, fat necrosis requiring hospitalization, or surgical treatment, were identified within 180 days after surgery. Risk factors for serious wound complications were determined using modified Poisson regression, with discrimination and calibration measures. Bootstrap validation was performed to correct for overfitting. RESULTS: Among 2159 mastectomy procedures, 1410 (65.3%) included immediate implant or flap reconstruction. Serious wound complications were identified after 237 (16.8%) mastectomy-plus-reconstruction and 30 (4.0%) mastectomy-only procedures. Independent risk factors for serious wound complications included immediate reconstruction, bilateral mastectomy, higher body mass index, depression, and smoking. The optimism-corrected C statistic of the risk prediction model was 0.735. CONCLUSIONS: Immediate reconstruction, bilateral mastectomy, obesity, depression, and smoking were significant risk factors for serious wound complications in this population of women undergoing mastectomy. Our risk prediction model can be used to counsel women before surgery concerning their individual risk of serious wound complications after mastectomy.
Subject(s)
Breast Neoplasms , Mammaplasty , Adult , Breast Neoplasms/complications , Breast Neoplasms/surgery , Female , Humans , Mammaplasty/adverse effects , Mammaplasty/methods , Mastectomy/adverse effects , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Retrospective Studies , Surgical Wound Infection/epidemiology , Surgical Wound Infection/etiology , Young AdultABSTRACT
BACKGROUND: Pseudomonas aeruginosa accounts for 7 to 22 percent of breast implant-associated infections, which can result in reconstructive failures and explantation. Investigating host-pathogen-device interactions in mice and patient samples will improve the understanding of colonization mechanisms, for targeted treatments and clinical guidelines. METHODS: Mice with and without implants were infected with PAO1 laboratory strain or BIP2 or BIP16 clinical strains and killed at 1 day or 7 days after infection to evaluate for colonization of implants and underlying tissues by means of colony-forming unit enumeration. Immunostaining was performed on mouse implants, human tissue expanders colonized by BIP2, and acellular dermal matrix colonized by BIP16. RESULTS: Colonization of tissues and smooth implants by P. aeruginosa was strain-dependent: at 1 day after infection, all strains acutely infected tissues with and without implants with colonization levels reflecting growth rates of individual strains. At 7 days after infection, PAO1 caused colonization of approximately 10 5 colony-forming units/100 mg of tissue but required implant presence, whereas in mice infected with BIP2/BIP16, colony-forming units were below the limit of detection with or without implants. Immunofluorescence staining of mouse implants, however, demonstrated continued presence of BIP2 and BIP16. Staining showed co-localization of all strains with fibrinogen, collagen I, and collagen III on mouse and human samples. CONCLUSIONS: The trajectory of P. aeruginosa in breast implant-associated infections was strain-dependent, and strains could exhibit acute symptomatic or chronic asymptomatic colonization. With strains causing clinical symptoms, the presence of an implant significantly worsened infection. For asymptomatic colonizers, further studies investigating their long-term impacts, especially during periods of immunosuppression in hosts, are needed.