Scientific Abstract Presentations: Breast Session 1 Thursday, October 15 Thu, Oct 15 1:30-3:00 p.m. CDT

Purpose: Infection remains one of the most common and consequential complications following implant-based breast reconstruction after mastectomy, with rates ranging from 1% to 35% (1). Standard preventive measures, including perioperative antibiotics and antiseptic irrigation, have not fully mitigated this risk. While prophylactic absorbable antibiotic beads have demonstrated efficacy in orthopedic settings, their role in implant-based reconstruction remains underexplored. This study aims to evaluate the impact of prophylactic absorbable antibiotic beads on infection rates, reconstructive loss, and overall outcomes.

Methods: This retrospective cohort study included patients who underwent primary implant-based breast reconstruction with partial subpectoral tissue expanders over a two-year period (2024-2025) at a single institution by a single surgeon. All patients received a contoured, perforated acellular dermal matrix (ADM), which served as an inferior pole sling. This created a retromuscular pocket. The experimental group received biodegradable calcium sulfate antibiotic beads (Stimulan ®) infused with 1g vancomycin and 240mg gentamicin in this pocket before tissue expander placement. The inferior border of the pectoralis major was then sewn to the ADM, and two postoperative drains were placed in the prepectoral space. The control group underwent primary partial subpectoral implant-based breast reconstruction with tissue expanders without antibiotic beads over a two-year period (2022-2023) at the same institution by the senior author. Both groups had expanders placed in the same fashion, with ADM and postoperative drains, and received perioperative and post-operative prophylactic antibiotics.

Results: 429 patients (757 breasts) were included. Over a two-year period, 189 patients (338 breasts) underwent implant-based breast reconstruction with prophylactic antibiotic beads, while 240 patients (419 breasts) served as historical controls. The average age was 49.7 years, the mean BMI was 26.2, and the mean mastectomy weight was 521.2 g. There were no statistically significant differences in age, BMI, or mastectomy weight between groups (p > 0.05, student t-test). The infection rate was 9.47% (32/338) in the antibiotic bead group, significantly lower than 19.33% (81/419) in the control group (p < 0.001, chi-square analysis). Total reconstructive loss was 6.21% (21/338) in the bead group compared to 14.08% (59/419) in the control group (p < 0.001, Fisher's exact test). Among reconstruction losses, 3.55% (12/338) of breasts in the bead group were lost due to infection, compared to 9.78% (41/419) in the control group, while 2.66% (9/338) of bead group breasts were lost due to soft tissue failure. Reoperation for infection was performed in 7.69% (26/338) of total reconstructed breasts, with 14 salvaged with surgical washout, 6 salvaged without surgery, and 12 ultimately resulting in temporary loss of reconstruction.

Conclusion: Prophylactic absorbable antibiotic beads were associated with significantly lower infection rates and reduced reconstructive loss in implant-based breast reconstruction. These findings suggest that beads may serve as an effective adjunct for infection prevention in breast reconstruction patients by providing localized antibiotic delivery. However, further studies are needed to validate their impact.

References: 1. Nelson, J, Mehrara, B, Coriddi, MR. Management of the Infected Tissue Expander. Plast Reconstr Surg. 2025;155(6):p961e-973e. doi:10.1097/PRS.0000000000011809

Background: Glucagon-like peptide-1 (GLP-1)-based medications are increasingly prescribed for type 2 diabetes and weight management, yet their impact on outcomes following autologous breast reconstruction (ABR) remains poorly defined. In abdominally-based ABR, surgical candidacy and postoperative outcomes are closely tied to body mass index and metabolic comorbidity. As GLP-1 based therapies expand surgical eligibility through weight optimization and improved glycemic control within the reconstructive population, GLP-1 perioperative implications warrant further investigation. This study evaluated the association between preoperative GLP-1 use and postoperative complications after immediate abdominally-based ABR.

Methods: We performed a retrospective cohort study of patients undergoing immediate abdominally-based ABR from September 2005 to July 2025. Inclusion required a recent hemoglobin A1c measurement relative to the day of surgery, which was analyzed as a quantitative measure of glycemic control rather than relying solely on diabetes diagnosis. Patients were grouped by preoperative GLP-1 exposure, comparing users with nonusers. Demographics, oncologic management, surgical details, and postoperative complications were compared between cohorts. Univariable analyses identified relevant covariates that were incorporated into multivariable logistic regression to determine whether GLP-1 exposure was independently associated with postoperative complications. Secondary analyses among GLP-1 users stratified outcomes first by medication type (semaglutide vs. tirzepatide) and then by preoperative discontinuation timing (≤ 10 days or >10 days prior to reconstruction), corresponding clinically to omission of one versus at least two weekly doses. Lastly, GLP-1 use was also assessed in a normoglycemic subgroup (HbA1c < 5.7%).

Results: Among 115 patients (193 breasts), 19 patients (36 breasts) received preoperative GLP-1-based medications and 96 patients (157 breasts) did not. On unadjusted analysis, overall and individual breast complication rates were comparable between GLP-1 users and nonusers. Delayed abdominal donor-site wound healing was more frequent among GLP-1 users; however, on adjusted multivariable analysis GLP-1 use was not independently associated with breast or abdominal donor-site complications (all P ≥ .079). In secondary analyses among GLP-1 users, medication type analyses demonstrated that tirzepatide use was associated with higher rates of nipple-areolar complex necrosis compared with semaglutide (P = .001). A shorter interval between GLP-1 discontinuation and surgery (≤10 days) corresponded with increased rates of breast fat necrosis (P = .049) and infection requiring oral antibiotics (P = .036) when compared to a discontinuation interval of >10 days. In the normoglycemic subgroup, breast outcomes remained comparable between GLP-1 users and nonusers, while delayed abdominal wound healing (P = .026) and donor-site fat necrosis (P = .025) were more frequent among GLP-1 users.

Conclusion: Preoperative GLP-1-based medication use was not independently associated with breast or abdominal donor-site complications following immediate ABR. Secondary analyses identified associations related to medication type, discontinuation timing, and select breast and donor-site outcomes. These findings suggest that preoperative GLP-1 use should not be considered a contraindication to immediate ABR. Rather, individualized preoperative assessment incorporating metabolic status, medication type, and perioperative timing may better inform risk stratification and surgical planning.

Breast cancer remains the second leading cause of cancer death among women in the United States. Mastectomy, a cornerstone of surgical management, may be performed using various techniques, including simple, skin-sparing, and nipple-sparing (NSM), and followed by immediate or delayed breast reconstruction. Although microsurgical success, such as flap viability, is well established, the extent to which objective surgical outcomes translate into patient-reported satisfaction remains unclear. This meta-analysis quantifies pooled microsurgical success rates and evaluates how reconstruction timing, surgical technique, and clinical factors influence BREAST-Q outcomes, integrating objective metrics with patient-centered perspectives to guide surgical planning and optimize recovery and satisfaction.

A systematic review and meta-analysis were conducted following the PRISMA guidelines. PubMed, Scopus, Cochrane Library, and Web of Science were searched for studies reporting breast reconstruction outcomes, complications, and patient-reported outcome measures (PROMs). Data extracted included patient demographics, reconstruction timing (immediate vs. delayed), reconstruction type (autologous vs. implant-based), mastectomy approach, complications, and BREAST-Q scores. Dichotomous outcomes were pooled using odds ratios, and continuous outcomes using weighted mean differences, both with 95% confidence intervals under a random-effects model. Subgroup analyses by mastectomy and reconstruction type, and meta-regression assessing the impact of complications on BREAST-Q scores were performed.

Of 345 identified articles, 46 met inclusion criteria, representing 21,961 total patients (immediate reconstruction: n = 15,559 (71%); delayed: n = 6,402 (29%)) and 24,035 breasts. Total and partial flap loss rates were low and did not significantly differ between immediate and delayed reconstruction. Immediate reconstruction was associated with modestly higher aesthetic satisfaction (mean difference 4.7 points, p < 0.05) and significantly higher psychosocial well-being at 6 months (72 ± 11 vs. 65 ± 13, p = 0.02); however, long-term breast satisfaction at ≥12 months was equivalent (78 ± 10 vs. 76 ± 12, p = 0.42). Early physical well-being was slightly lower following immediate reconstruction (65 ± 12 vs. 70 ± 11, p = 0.03), whereas delayed reconstruction demonstrated greater improvement from baseline, resulting in comparable long-term chest well-being. NSM was consistently associated with higher psychosocial, sexual, and breast satisfaction scores than skin-sparing or simple/total mastectomy (p < 0.01), independent of reconstruction timing. Major complications negatively affected physical well-being (p < 0.01), but did not significantly impact breast satisfaction.

Microsurgical breast reconstruction demonstrates consistently high flap success rates, irrespective of timing. Immediate reconstruction confers early psychosocial advantages, whereas delayed reconstruction achieves comparable long-term patient-reported outcomes. Mastectomy-type, particularly nipple-sparing approaches, emerges as a stronger determinant of patient satisfaction than reconstruction timing. Additionally, complications predominantly impact physical well-being rather than aesthetic satisfaction, suggesting that patients prioritize final reconstructive outcomes over early morbidity. These findings underscore the importance of comprehensive preoperative patient education regarding surgical options, aesthetic expectations, and recovery trajectories. Emphasis on individualized surgical planning that balances oncologic safety, surgical technique, and timing is critical to optimizing both short-term recovery and long-term satisfaction.

Introduction: While prior abdominal surgery is often viewed as a constraint in deep inferior epigastric perforator (DIEP) flap breast reconstruction, its specific impact on perforator architecture remains under-characterized. We aimed to utilize CT Angiography (CTA) to compare perforator quantity, quality, and spatial distribution between patients with and without a history of abdominal surgery, specifically evaluating the "delay phenomenon" across different surgical approaches.

Methods: A retrospective analysis of 76 CTA scans from DIEP flap candidates was performed. Perforators (larger than 1mm) were mapped using x (horizontal) and y (vertical) coordinates relative to the umbilicus in centimeters.. Incision type (minimally invasive or open) and total abdominal operations were recorded. Perforators were classified into medial or lateral rows by their true anatomical DIEA branching pattern, and assigned to periumbilical or lower abdominal zones based on a 3.5-cm vertical cutoff. Dominant perforators were defined as greater than 2mm. To isolate surgical trauma from physiological expansion, parous and nulliparous cohorts were compared.

Results: History of abdominal surgery did not significantly reduce total perforator count (p >0.30). Interestingly, patients with prior surgery demonstrated a significantly higher density of dominant periumbilical perforators compared to controls (2.15 ± 1.32 vs. 1.32 ± 1.11, p = 0.015). When stratifying by approach, laparoscopic patients exhibited a focal deficit of dominant vessels in the lower abdomen compared to the open surgery cohort (0.71 ± 0.86 vs. 1.67 ± 1.13, p = 0.003). While pregnancy increased the total number of periumbilical vessels (2.12 ± 1.36 vs. 1.33 ± 0.97, p = 0.029), it did not recruit larger (> 2mm) vessels, suggesting that the dominant vessel recruitment seen in the surgical group is a result of compensatory delay rather than just tissue expansion.

Conclusion: While prior abdominal surgery and pregnancy significantly reorganize the DIEA perforator architecture, they do not compromise the viability of the abdominal donor site. Our findings demonstrate that the 'scarred' abdomen undergoes predictable vascular adaptations, often resulting in a compensatory recruitment of periumbilical vessels. By utilizing granular CTA data, surgeons can transition from a binary risk assessment of abdominal scars to a proactive, patient-specific mapping strategy. This approach optimizes perforator selection and reinforces the safety of DIEP flap reconstruction across diverse surgical histories.

Background: SAVI Scout® radar-guided localization has emerged as an alternative to traditional wire-guided localization for nonpalpable breast lesions. However, comparative outcome data in patients undergoing oncoplastic breast-conserving surgery with reduction techniques remain limited. This study compares patient characteristics and surgical outcomes between SAVI Scout® and wire-guided localization in the oncoplastic reduction setting.

Methods: A retrospective review was performed of consecutive patients undergoing oncoplastic reduction at the time of breast-conserving surgery between February 2010 and April 2025 using a single-institution database. Patients were stratified by localization technique into wire-guided and SAVI Scout®–guided cohorts. Outcomes analyzed included demographic and tumor characteristics, margin status, re-excision rates, postoperative complications, recurrence, and both lumpectomy specimen and total ipsilateral resection weights. Continuous variables were compared using Welch's t tests, and categorical variables using chi-square or Fisher's exact tests, as appropriate.

Results: A total of 611 eligible procedures were identified, including 402 wire-guided and 209 SAVI-localized cases. Patients in the SAVI cohort were slightly older (59.0 ± 10.4 vs 56.9 ± 10.7 years, p = 0.0189), while BMI was similar between groups (32.9 ± 7.3 vs 33.3 ± 7.4 kg/m², p = 0.482). Mean follow-up was longer in the wire cohort (2.73 ± 2.17 vs 1.41 ± 1.10 years, p < 0.001). Tumor size and closest margin distance were comparable between cohorts (1.98 ± 1.72 vs 2.08 ± 2.41 cm, p = 0.579; 0.44 ± 0.46 vs 0.47 ± 0.61 cm, p = 0.559). Initial lumpectomy specimen weight was significantly lower in the SAVI cohort (121.6 ± 117.3 g vs 191.4 ± 210.3 g, p < 0.001), while total ipsilateral resection weight did not differ (482.5 ± 598.8 g vs 497.7 ± 426.1 g, p = 0.76). Re-excision for positive margins occurred less frequently following SAVI localization (1.4% [n = 3] vs 5.7% [n = 23], p = 0.013). Overall complication rates (17.4% vs 16.3%, p = 0.721) and major complication rates (4.3% vs 7.0%, p = 0.191) were similar. Infection requiring antibiotics and/or operative washout was more common after wire-guided localization (8.2% [n = 33] vs 2.4% [n = 5], p = 0.005). Recurrence rates were low and did not differ significantly between groups (0.5% vs 2.7%, p = 0.10).

Conclusions: In oncoplastic reduction surgery, SAVI Scout® localization was associated with significantly smaller lumpectomy specimens, reduced re-excision and infection rates, and comparable complication and recurrence outcomes relative to wire-guided localization. Preservation of total ipsilateral resection volume suggests that SAVI Scout® supports effective tumor excision without compromising reconstructive goals, supporting its use as a safe and effective alternative to wire-guided localization in the oncoplastic breast-conserving setting.

Purpose: Breast surgery encompasses a broad spectrum of oncologic and reconstructive procedures performed in patients with heterogeneous physiologic risk profiles. Existing perioperative risk calculators rely largely on traditional regression approaches and often demonstrate limited discrimination, calibration, and procedure-specific applicability. The purpose of this study was to develop and validate interpretable machine learning (ML) models capable of predicting major 30-day postoperative adverse outcomes following oncologic and reconstructive breast surgery in a large national cohort, in addition to deploying these models as an accessible clinical decision-support tool to facilitate individualized risk estimation and perioperative decision-making.

Methods: A retrospective cohort study was performed using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from 2008-2024. Adult patients undergoing disease-directed breast surgery were identified, yielding 737,730 eligible cases. 83 demographic, clinical, laboratory, and operative variables were incorporated into standardized preprocessing pipelines. Data were randomly divided into training (70%), validation (15%), and held-out test (15%) cohorts. Five modeling approaches-logistic regression, XGBoost, LightGBM, neural networks, and stacked ensemble models-were trained to predict five prespecified 30-day outcomes: surgical complications, medical complications, unplanned reoperation, venous thromboembolism (VTE), and mortality. Model evaluation emphasized clinically meaningful risk stratification using lift, with secondary assessment of discrimination (AUROC), feature attribution (SHAP), and calibration metrics including Integrated Calibration Index (ICI) and Brier score.

Results: Among 737,730 patients (median age 56 years; median BMI 28.2 kg/m²), postoperative event rates included surgical complications (3.9%), unplanned reoperation (3.3%), medical complications (0.7%), VTE (0.2%), and mortality (0.1%). Final outcome-specific models demonstrated strong performance on the independent test cohort. AUROC values ranged from 0.73 to 0.88 across outcomes, indicating strong discrimination. Calibration was excellent, with ICI values between 0.002 and 0.016 and Brier scores ranging from 0.001 to 0.035. Risk stratification demonstrated progressive enrichment of adverse events across predicted risk tiers. Observed event rates increased from 0.43% to 4.61% for medical complications (maximum lift 6.85), 1.45% to 14.74% for unplanned reoperation (lift 4.45), 1.16% to 15.49% for surgical complications (lift 4.01), 0.11% to 1.76% for VTE (lift 8.66), and 0.02% to 1.62% for mortality (lift 29.46). High-risk strata represented approximately 1-7% of patients yet captured disproportionate event burdens, including 14.3% of medical complications, 21.4% of reoperations, 28.7% of surgical complications, 18.2% of VTE events, and 42.6% of deaths. Gradient-boosted tree models (XGBoost and LightGBM) consistently demonstrated superior concentration of high-risk patients compared with alternative architectures. The final models were deployed as PRO-BREAST (https://pro-breast.streamlit.app), a publicly accessible web-based risk calculator that generates individualized complication risk estimates along with patient-specific drivers of predicted risk.

Conclusions: In this large national analysis, interpretable machine learning models accurately predicted major postoperative complications following oncologic and reconstructive breast surgery while maintaining excellent calibration and clinically meaningful risk stratification. Deployment of these models as the PRO-BREAST calculator enables individualized, transparent risk assessment incorporating both patient and procedural complexity. These findings support the integration of interpretable ML-based prediction tools into perioperative counseling and surgical planning workflows, although prospective external validation remains necessary prior to widespread clinical adoption.

Purpose: Capsular contracture remains a leading cause of revision after implant-based breast surgery. While radiation and smoking are recognized risk factors, a history of hypertrophic scars has not been evaluated at scale despite potential overlap in fibroproliferative wound healing pathways. We hypothesized that a history of hypertrophic scar would be associated with increased risk of subsequent capsular surgery following breast implant placement.

Methods: A retrospective propensity-matched cohort study was performed using the TriNetX research network. Adults undergoing implant placement were identified using CPT 19325 (augmentation), 19340 (immediate implant insertion), or 19342 (delayed implant insertion). Patients with prior capsular contracture (T85.44) were excluded. Cohort A included patients with hypertrophic scar history (L91.0) prior to index; Cohort B had no pre-index history of hypertrophic scar. Cohorts were propensity-matched 1:1. Outcomes were assessed within 4 years of implant placement. The primary outcome was capsular surgery defined as CPT 19370 (capsulotomy) or 19371 (capsulectomy). Risk ratios and risk differences were calculated between groups. Kaplan–Meier analysis was performed using log-rank testing and a hazard ratio was calculated. A multivariable Cox proportional hazards model was used to adjust for age, BMI, diabetes, tobacco use, radiation, chemotherapy, connective tissue disease, and breast malignancy.

Results: There were 433 patients in each cohort after matching. Subsequent capsular surgery occurred in 56 (12.93%) patients with hypertrophic scar history versus 28 (6.47%) without (risk difference 6.47%, 95% CI 2.55–10.39; RR 2.00, 95% CI 1.30–3.09; p=0.001). Kaplan–Meier analysis demonstrated an increased hazard of capsular surgery in the hypertrophic scar cohort (HR 1.99, 95% CI 1.26–3.13; log-rank p=0.002), with no evidence of proportional hazards violation (p=0.161). In the multivariable Cox model, hypertrophic scar history remained independently associated with capsular surgery (HR 1.85, 95% CI 1.42–2.41; p<0.001). Radiation, tobacco use, and breast malignancy were also significant predictors (all p<0.01).

Conclusion: A history of hypertrophic scars was independently associated with higher risk of subsequent capsulectomy or capsulotomy after breast implant placement. These findings may inform risk stratification and surveillance in implant-based breast surgery for patients with a history of hypertrophic scarring.

Background: Perforator selection during deep inferior epigastric perforator (DIEP) flap harvest remains one of the most technically challenging aspects of autologous breast reconstruction. Although medial row perforators have increased risk of fat necrosis, they have traditionally been favored due to presumed larger perfusion territories that cross the midline to supply the contralateral hemiabdomen. Lateral row perforators primarily supply the ipsilateral hemiabdomen and offer technical advantages, including shorter intramuscular dissection, decreased operative time, and positive postoperative outcomes. While perforator selection has relied on careful consideration during intraoperative and preoperative vessel evaluation, a standardized method has yet to be adopted. This study evaluated a novel, algorithmic approach prioritizing lateral row perforators guided by intraoperative perfusion assessment.

Methods: A retrospective review was performed of all DIEP flaps conducted by a single surgeon between January 2021 and November 2025. Flaps were categorized as either lateral row based only or having medial row involvement. Patient demographics, surgical history, oncological treatment, flap characteristics, and detailed operative and postoperative data were collected through electronic medical records. A reproducible sequence algorithm was developed to determine which perforator is preferred. Patient demographics, operative variables, and postoperative outcomes were compared.

Results: A total of 184 DIEP flaps in 122 patients were included. Lateral row perforators alone supported 127 flaps (69%), while 57 flaps (31%) required medial row involvement. Median patient age was slightly lower in the lateral row-only group (50.7 vs 53.6 years, p=0.013) and a higher proportion of never- smokers were in the lateral row group (84.3% vs. 68.4%, p=0.014). Lateral row-based flaps required fewer perforators (median 2 vs. 3, p<0.001) but the distribution of dominant perforator size did not differ significantly between groups. There were no total flap losses, however, umbilical necrosis occurred exclusively in the medial row group (8.8% vs 0%, p=0.002).

Conclusion: Lateral row perforators can reliably support DIEP flaps in most cases. An algorithmic approach incorporating superficial venous drainage and intraoperative perfusion assessment simplifies dissection, reduces morbidity, and maintains excellent outcomes without reliance on preoperative perforator imaging.

INTRODUCTION: Tissue expander–based immediate breast reconstruction (TE-IBR) following mastectomy often utilizes acellular dermal matrix (ADM), but ADM use has been linked to higher rates of infection and seroma. This has led to variation in postoperative antibiotic practices, despite antimicrobial stewardship guidelines recommending discontinuation within 24 hours. Contemporary multicenter evidence on optimal antibiotic duration in ADM-assisted TE-IBR is limited. This study leverages a large real-world database to evaluate whether extending postoperative antibiotics beyond 24 hours decreases the risk of infection or complications following ADM-assisted TE-IBR.

METHODS: Using the TriNetX Global Collaborative Network, this retrospective cohort study identified adult women who underwent ADM-assisted tissue expander–based immediate breast reconstruction (TE-IBR) (CPT 19357, 15777; ICD-10 Z42.1) between January 2006 and December 2025 across 170 healthcare organizations. Inclusion required receipt of prophylactic systemic antibiotics on the day of surgery. Patients with systemic antibiotic use within 30 days prior to surgery were excluded. The index event was tissue expander placement with ADM. Patients were stratified into mutually exclusive cohorts based on postoperative antibiotic duration: short (≤1 day) versus prolonged (>1 day). To minimize confounding, 1:1 propensity score matching was performed, balancing demographics (age, race, ethnicity), comorbidities (BMI, tobacco use, diabetes, hypertension, hyperlipidemia, kidney disease, immune disorders, breast malignancy), and infection risk modifiers (prior breast biopsy, biologic implants, immunosuppressants, corticosteroids, chemotherapy, radiotherapy). The primary outcome was localized infection at 30, 60, and 90 days postoperatively. Secondary outcomes included wound dehiscence, seroma, hematoma, severe infection, expander-related complications, explantation, and overall complication burden. Risk ratios (RR) with 95% confidence intervals (CI) were calculated, and a two-sided p-value <0.05 was considered statistically significant.

RESULTS: A total of 4,647 patients met inclusion criteria (mean age 50.7 ± 11.4 years); 715 (15.4%) received prolonged postoperative antibiotics, while 3,932 (84.6%) received ≤24 hours of antibiotics. Before matching, the prolonged group had higher rates of diabetes, hypertension, chemotherapy, radiation, and corticosteroid use. After 1:1 propensity score matching, 710 well-balanced pairs were analyzed (standardized differences <0.1). Localized infection rates were similar between groups at 30 days (2.68% vs 2.54%; RR 1.06, 95% CI 0.56–1.99; p=0.868), 60 days (4.08% vs 3.94%; p=0.893), and 90 days (4.37% vs 5.07%; p=0.532). Severe infection, expander removal, and overall complication rates did not differ at any time point (all p>0.05). The composite outcome of seroma or hematoma was higher at 60 days in the prolonged group (4.93% vs 1.97%; RR 2.50; p=0.002), with no differences at 30 or 90 days.

CONCLUSIONS: In this large multicenter cohort, extending postoperative antibiotics beyond 24 hours did not reduce infection, expander loss, or overall complication rates following ADM-assisted TE-IBR. These findings align with prior randomized data demonstrating no benefit to extended prophylaxis (1). Although extended antibiotics may reflect early clinical concern, no protective effect was observed. These findings support limiting postoperative prophylaxis to ≤24 hours and reinforce antibiotic stewardship in implant-based breast reconstruction.

REFERENCES: 1. Phillips BT, Fourman MS, Bishawi M, et al. Are Prophylactic Postoperative Antibiotics Necessary for Immediate Breast Reconstruction? Results of a Prospective Randomized Clinical Trial. J Am Coll Surg. 2016;222(6):1116-1124. doi:10.1016/j.jamcollsurg.2016.02.018

Background: Neurotization during DIEP flap breast reconstruction seeks to restore sensation via nerve coaptation, but the benefit of adding a lateral coaptation target is unclear. We compared early sensory recovery after single- versus dual-nerve coaptation using pressure-specified sensory device (PSSD) testing.

Methods: In a prospective single-institution cohort (2022-present) of immediate DIEP reconstructions performed by a single surgeon, breasts undergoing single neurotization (2022-2023) were compared with breasts undergoing dual neurotization (2024-present). Tactile thresholds (0-100 g/mm²) were converted to sensation scores (0-100) and assessed at 3, 6, 9, and 12 months. Between-group comparisons were performed on raw sensation scores at each timepoint. Regional comparisons were Holm-adjusted within timepoints. Percent recovery relative to each breast's preoperative baseline was calculated descriptively using paired subjects.

Results: Demographic and surgical characteristics were similar between cohorts (Dual: n = 49 breasts; Single: n = 44 breasts), including age (p = 0.977), BMI (p = 0.877), mastectomy weight (p = 0.660), and nipple-sparing mastectomy rate (p = 1.000).

At 9 months, dual neurotization demonstrated significantly greater composite sensation than single (44.7 vs 18.6; Holm-adjusted p = 0.0045). No between-group differences were observed at 3, 6, or 12 months. At 9 months, regional analyses revealed significantly greater recovery in the outer-inferior (36.4 vs 4.2; p = 0.0069), outer-superior (66.8 vs 28.7; p = 0.0109), and inner-lateral (37.3 vs 9.0; p = 0.0468) regions after Holm adjustment. Descriptively, dual patients recovered 58% of baseline composite sensation at 9 months compared with 26% in single nerve patients. By 12 months, dual nerve patients continued to show greater recovery (66% vs 58% of baseline).

Patient-reported outcomes favored dual coaptation, with higher BREAST-Q Physical Well-Being: Chest scores at 3 months (81.5 ± 19.8 vs 62.5 ± 12.9; p = 0.038).

Conclusions: Dual nerve coaptation in DIEP flap breast reconstruction was associated with significantly improved sensory recovery at 9 months, with regional patterns consistent with the additional lateral coaptation. Larger cohorts with longer follow-up are needed to confirm whether dual coaptation confers durable advantages beyond 12 months.

Introduction Loss of sensation to the chest and nipple-areola complex (NAC) after mastectomy results from transection of cutaneous intercostal nerve branches, with limited and unreliable spontaneous recovery across tactile, thermal, nociceptive, and erogenous modalities. Targeted Nipple Reinnervation (TNR) has demonstrated consistent benefit in restoring postoperative sensation across transgender, oncologic, and gynecomastia populations. Comprehensive assessment of sensory recovery requires multimodal quantitative sensory testing (QST), including monofilament, pinprick, thermal, vibration, pressure, and two-point discrimination (2PD), but the time, equipment, and expertise required limit routine clinical implementation. Semmes-Weinstein (SW) monofilament testing offers a rapid, inexpensive, and widely accessible alternative. We aimed to determine whether SW thresholds can serve as a surrogate marker for multimodal sensory recovery following chest neurotization. Methods This multicenter prospective cohort study enrolled 158 patients (1,248 testing sites) undergoing chest neurotization with TNR at Weill Cornell Medicine and Massachusetts General Hospital (January 2023 to January 2024). Comprehensive QST, including SW monofilaments, pinprick, cold and warm detection, heat pain, pressure pain, vibration, and 2PD, was performed preoperatively and at a mean 10.5-month follow-up using standardized DFNS protocols across both institutions. Sensory measurements were collected at 8 chest-wall and 5 NAC locations. Postoperative SW thresholds were grouped into four recovery categories: excellent (2.83), good (3.61-4.31), moderate (4.56), and poor (5.07-6.65). Between-group comparisons used Kruskal-Wallis tests; pre-to-postoperative changes were assessed with Wilcoxon signed-rank tests. Results Preoperative sensory thresholds were comparable across recovery groups, though 2PD and pressure pain thresholds showed greater baseline variability, with better recovery groups demonstrating lower baseline values. Postoperatively, sites with excellent SW recovery (2.83) demonstrated near-normal function across all modalities: preserved low-force pinprick detection, normalized cold and warm detection thresholds, appropriate heat pain thresholds, and high vibration scores. Good recovery sites (3.61-4.31) showed partially preserved thermal, nociceptive, and vibratory function with mildly reduced low-force pinprick responses. Moderate recovery sites (4.56) exhibited further reductions in pinprick responsiveness, elevated thermal thresholds, and increased pressure pain thresholds. Poor recovery sites (5.07-6.65) demonstrated pronounced deficits including near-absent low-force pinprick detection, markedly elevated cold and warm detection thresholds, and substantially increased pressure pain thresholds. Cold detection, warm detection, heat pain, pressure pain, and vibration all differed significantly across SW recovery groups at both chest and NAC sites (all p<0.05). 2PD was the sole exception, remaining stable across all SW categories with no significant between-group difference at the chest (p>0.05), likely reflecting insufficient resolution for sensory assessment at this anatomical site. Discussion SW monofilament thresholds reliably reflect multimodal sensory recovery following chest neurotization, tracking tactile, thermal, nociceptive, vibratory, and pressure domains across recovery strata, with the notable exception of 2PD, which showed poor discriminative ability at the chest and NAC. The parallel recovery of SW categories with small-fiber–mediated modalities suggest coordinated regeneration across afferent fiber populations following TNR. As the first multicenter study to validate SW testing against comprehensive QST in this population, these findings support SW monofilament testing as a practical, efficient surrogate for comprehensive sensory assessment, enabling standardized outcome benchmarking across institutions and lowering barriers to routine postoperative sensory evaluation following chest neurotization.

Background Glucagon-like peptide-1 (GLP-1) receptor agonists are increasingly utilized for medical weight loss. GLP-1–associated weight loss has been reported to contribute to changes to the collagen and elastin soft-tissue components, raising concern for breast reconstruction outcomes. However, its impact on postoperative reoperation rates and implant-related complications remains unclear. This study evaluated long-term outcomes of breast reconstruction among overweight and obese patients using GLP-1 receptor agonists for weight loss. We hypothesized that GLP-1 receptor agonist–associated weight loss would be associated with increased rates of implant-related complications and reoperations following breast reconstruction.

Methods The TriNetX National Research Database was queried to identify patients who underwent breast reconstruction between 2015 and 2023. Two cohorts were defined: patients who used weight-loss approved GLP-1 receptor agonists within the first two years following surgery and patients without GLP-1 use. Propensity score matching was performed for demographic and clinical variables. Outcomes at two- and three-years included overall reoperation (mastopexy, reconstruction revision, fat grafting, implant explant, capsulectomy, and capsular revision), capsular contracture, and lymphedema among implant-based reconstruction patients.

Results After propensity score matching, 770 patients were included (385 GLP-1 users and 385 non-users). At both two- and three-years postoperatively, GLP-1 use was associated with a significantly lower risk of overall reoperation (23.9% vs 46.2%, p<0.0001 and 30.2% vs 54.9, p<0.0001, respectively), mastopexy (2.7% vs 7.1%, p=0.006 and 3.8% vs 7.9%, p=0.018, respectively), and reconstruction revision (16.3% vs 31.3%, p < 0.0001 and 20.1% vs 37.5%, p<0.0001, respectively). Among patients undergoing tissue-expander/implant (TE/I) reconstruction, GLP-1 use was also associated with a significantly lower risk of capsular contracture at both time points (12.5% vs 31.9%, p<0.0001 and 14.5% vs 35.5%, p<0.0001, respectively).

Conclusion This is the first large database study demonstrating that GLP-1 receptor agonist use may be associated with decreased risks of reoperation and capsular contracture following breast reconstruction. Thus, suggesting potential protective effects of GLP-1 therapy on overweight and obese patients, warranting further investigation into underlying mechanisms and perioperative implications.

Background Glucagon-Like Peptide-1 (GLP-1) receptor agonists are increasingly prescribed for metabolic disease and chronic weight management. As the number of surgical patients receiving GLP-1 therapy continues to rise, concerns have emerged regarding the potential effects of the drug class on perioperative and postoperative outcomes. In breast and plastic surgery, particular attention has been directed toward the impact of GLP-1 therapy on wound healing, with recent studies reporting higher rates of wound-related complications among GLP-1 users following elective plastic surgical procedures. However, evidence regarding the impact of preoperative GLP-1 use on postoperative outcomes following oncoplastic breast surgery, which is a form of breast conservation surgery that combines oncologic resection with plastic surgery reconstruction techniques, remains limited.

Methods We conducted a single-center retrospective cohort study of adult patients who underwent oncoplastic breast surgery between 2022 and 2025. Patients were stratified into two cohorts based on reconstructive technique following partial mastectomy: volume displacement (VD), defined as closure of the oncologic resection defect using adjacent tissue transfer techniques of the remaining ipsilateral breast tissue, and volume replacement (VR), defined as reconstructing the oncologic defect with locoregional flaps. Patients were further stratified according to preoperative GLP-1 receptor agonist use. The primary outcome was any 30-day postoperative complication, including wound complications (infection, dehiscence, seroma, hematoma, fat necrosis), pedicle or flap failure, nipple loss, hypertrophic scarring, and reoperation. Multivariable logistic regression was used to assess the association between GLP-1 use and postoperative complications, adjusting for age and body mass index (BMI) in both cohorts and total resected tissue weight (per 500 g) in the VD cohort. Sensitivity analyses were conducted.

Results Among 224 patients who underwent VD reconstruction (20 GLP-1 users), 39 experienced at least one postoperative complication (5 GLP-1 users). Among 137 patients who underwent VR reconstruction (11 GLP-1 users), 17 experienced at least one postoperative complication (3 GLP-1 users). GLP-1 users had higher baseline BMI, higher rates of diabetes, and greater tissue resection volume than non-users. In adjusted analyses, preoperative GLP-1 use was not independently associated with increased odds of 30-day postoperative complications in the VD cohort (OR 0.91, 95% CI 0.24-2.81, p = 0.87) or the VR cohort (OR 2.83, 95% CI 0.55-11.90, p = 0.17). All sensitivity analyses yielded similar results. Most complications were minor wound-related events, with no flap or pedicle failure and no nipple loss observed. Interpretation is limited by the small number of GLP-1 users and low event rates.

Conclusions Preoperative GLP-1 receptor agonist use was not independently associated with increased 30-day postoperative complications following oncoplastic breast surgery using volume displacement or volume replacement techniques. Larger prospective studies are needed to confirm these findings and further characterize postoperative risk in this growing patient population.

Background: Oncoplastic reduction mammaplasty offers improved aesthetic outcomes through enhanced symmetry in breast cancer patients pursuing breast conservation. While the associations between neoadjuvant chemotherapy, postoperative complications, and timing to adjuvant radiation have been well studied, the results have been inconclusive. Further, the implications of newer systemic immunotherapy that are increasingly integrated into neoadjuvant regimens remains unclear. Therefore, we aimed to investigate the impacts of new systemic neoadjuvant therapies (NAT) on surgical outcomes and on timing to adjuvant radiation treatment.

Methods: We performed a retrospective review of patients who underwent oncoplastic reduction mammoplasty from 2020 to 2024. Demographics, operative techniques, surgical pathology, and outcomes were collected. Patients were first categorized by receipt of neoadjuvant chemotherapy. Subsequent subanalyses compared patients who received anti-programmed death (PD)-1 inhibitors to those who did not. Radiation delay was defined as >12weeks to the start of treatment from operative date. Bivariate analyses were performed with chi square, Mann-Whitney, and independent t-tests. Multivariable logistic regression models were then constructed to assess whether NAT types were independently associated with surgical outcomes and adjuvant radiation timing. Stata 18.0 was used for all statistical analyses.

Results: Of the 410 patients undergoing oncoplastic reduction, 114 patients (28%) received neoadjuvant chemotherapy, while 296 patients (72%) did not. These patients were significantly younger (p<.0001), had lower BMI (p=0.0159), lower incidence of hypertension (p=0.001), hyperlipidemia (p=0.02), and cardiac comorbidities (p=0.031). Incision type, defined as wise, vertical, or other, (p=0.06) and pedicle type, defined as superomedial, inferior, or other, (p=0.053) approached statistical significance and were also included in the logistical regression. Cancer histology (p=0.003) and grade (p=0.002) were significantly different between groups; although lumpectomy volume was not.

Receipt of neoadjuvant chemotherapy was associated with decreased rates of radiation delays (p=0.051), overall complications (p=0.005), and wound healing delays (p=0.01). On multivariable logistic regression, BMI was predictive of overall complications (OR: 1.12; CI: 1.04-1.20; p=0.002) and of wound healing delays (OR: 1.19; CI: 1.08-1.30; p<0.001). Hypertension was found to be inversely associated with wound healing delays (OR: 0.21; CI: .05-.78; p=0.02). No independent predictors of radiation delay were identified on multivariable regression.

Those who received neoadjuvant chemotherapy were further stratified by concurrent receipt of a PD-1 inhibitor. 20 patients (18%) received a PD-1 inhibitor, while 94 patients (82%) did not. No significant differences in demographics or surgical details were identified; however, tumor grade was significantly associated with PD-1 inhibitor treatment (p=0.03). PD-1 inhibitor use was not independently associated with any postoperative complication nor with delays to radiation treatment.

Conclusion: This is the most comprehensive analysis of this patient population to date, integrating reduction techniques, tumor size, histology, and neoadjuvant treatment regimens. Our data suggests that neoadjuvant immunotherapy, such as PD-1 inhibitors, is not associated with increased risk of surgical complications or delays to radiation, supporting the safety of oncoplastic reduction mammoplasty in this patient population. In future analyses, we aim to integrate targeted therapies as a sub-group analysis and expand on our analysis of re-excision rates.