Breast-Conserving Therapy is Associated with Improved Survival Without an Increased Risk of Locoregional Recurrence Compared with Mastectomy in Both Clinically Node-Positive and Node-Negative Breast Cancer Patients.

INTRODUCTION: Randomized trials demonstrated equivalent survival between breast-conserving surgery combined with radiotherapy (BCT) and mastectomy alone. Contemporary retrospective studies using pathological stage have reported improved survival with BCT. However, pathological information is unknown before surgery. To mimic real-world surgical decision-making, this study assesses oncological outcomes by using clinical nodal status. METHODS: Female patients aged 18-69 years who were treated with upfront BCT or mastectomy between 2006 and 2016 for T1-3N0-3 breast cancer were identified by using prospective, provincial database. The patients were divided into clinically node-positive (cN+) and node-negative (cN0) strata. Multivariable logistic regression was used to assess the effect of local treatment type on overall survival (OS), breast cancer-specific survival (BCSS), and locoregional recurrence (LRR). RESULTS: Of 13,914 patients, 8228 had BCT and 5686 had mastectomy. Mastectomy patients had higher-risk clinicopathological factors: pathologically positive axillary staging was 21% in BCT and 38% in mastectomy groups. Most patients received adjuvant systemic therapy. For cN0 patients, 7743 had BCT and 4794 had mastectomy. On multivariable analysis, BCT was associated with improved OS (hazard ratio [HR] 1.37, p < 0.001) and BCSS (HR 1.32, p < 0.001), whereas LRR was not different between the groups (HR 0.84, p = 0.1). For cN+ patients, 485 had BCT and 892 had mastectomy. On multivariable analysis, BCT was associated with improved OS (HR 1.46, p = 0.002) and BCSS (HR 1.44, p = 0.008), whereas LRR was not different between the groups (HR 0.89, p = 0.7). CONCLUSIONS: In the era of contemporary systemic therapy, BCT was associated with better survival than mastectomy, without an increased risk of locoregional recurrence for both cN0 and cN+ presentations.

Models for Implant-Induced Capsular Contracture Post Breast Cancer Surgery.

Capsular contracture is a painful deformation of scar-tissue that may form around an implant in post-breast cancer reconstruction or cosmetic surgery. Inflammation due to surgical trauma or contamination in the tissue around the implant could account for recruitment of immune cells, and transdifferentiation of resident fibroblasts into cells that deposit abnormally thick collagen. Here we examine this hypothesis using a mathematical model for interacting macrophages, fibroblasts, myofibroblasts, and collagen. Our model demonstrates that cellular response can, together with inflammatory cell recruitment, account for prognoses.

Methods of Recruitment for Surgical and Perioperative Randomized Controlled Trials: A Rapid Review.

Due to the complex nature of surgical randomized controlled trials (RCTs), reaching target recruitment can be challenging. The primary objective was to report on characteristics of successful pilot surgical and perioperative RCTs and the methodological strategies implemented to optimize recruitment. The secondary objective was to provide recommendations for successful recruitment strategies for future surgical RCTs. Ovid MEDLINE, Ovid EMBASE, and Web of Science (via Ovid) databases were searched from 2012 to 2022. This review included surgical and perioperative pilot studies that met their recruitment targets. Study and recruitment characteristics were summarized, and potential relationships between study design and recruitment rate were assessed. Optimized recruitment strategies were extracted when reported. Of 4156 total articles identified, 255 underwent full-text screening, and 52 articles were included. Of the included pilot studies, 21% (n = 11) did not indicate a target sample size or recruitment rate. Recruitment methods were minimally reported in pilot studies for perioperative or surgical RCTs. Strategies to optimize recruitment included internal iterative evaluations of the recorded recruitment appointments and staged introduction of the study. Recruitment rate was not associated with invasiveness of intervention or burden of participation. Patient involvement is absent from current reports on methodological design and offers valuable opportunity to optimize recruitment. Recruitment strategies in perioperative and surgical RCTs can be optimized with iterative qualitative evaluation of the recruitment methods with input from the interdisciplinary research team.

Implications of the COVID-19 Pandemic on Immediate Breast Reconstruction Access.

AIMS: As a result of COVID-19, there have been restrictions on surgical interventions across Canada. Immediate breast reconstruction (IBR), while an essential component of cancer care, is classified as elective surgery and therefore has been restricted in access over the course of the pandemic. The purpose of this study was to compare wait times for breast cancer patients undergoing surgical intervention for IBR before and since the COVID-19 pandemic. METHODS: This was a retrospective cross-sectional study of consecutive patients who underwent IBR between July 2018 and October 2021 by 5 plastic surgeons at a single Canadian health center. Wait times to consultation and surgical intervention between pre- and post-COVID cohorts were analyzed. RESULTS: A total of 161 patients met inclusion criteria. For ablative surgery, there was no difference in wait times to surgical oncology consultation (14.0 ± 12.3 vs 14.0 ± 11.0 days, P = 0.991) and surgical intervention with IBR (41.0 ± 49.8 vs 35.0 ± 58.0 days, P = 0.621) between the pre- and post-COVID cohorts. For breast reconstruction, while time to consultation with plastic surgery (12.5 ± 14.8 vs 11.0 ± 12.8 days, P = 0.775) remained unchanged, usage of autologous techniques was reduced [n = 13 (16%) vs n = 2 (2%), P = 0.006], and time to second-stage alloplastic reconstruction increased (230 ± 102 vs 325 ± 224 days, P = 0.044) post-COVID. CONCLUSIONS: Swift adoption of evidence driven protocols has resulted in comparable wait times for breast cancer ablative procedures. However, utilization of autologous techniques and wait times to second-stage reconstructions have increased.

Automated medical chart review for breast cancer outcomes research: a novel natural language processing extraction system.

BACKGROUND: Manually extracted data points from health records are collated on an institutional, provincial, and national level to facilitate clinical research. However, the labour-intensive clinical chart review process puts an increasing burden on healthcare system budgets. Therefore, an automated information extraction system is needed to ensure the timeliness and scalability of research data. METHODS: We used a dataset of 100 synoptic operative and 100 pathology reports, evenly split into 50 reports in training and test sets for each report type. The training set guided our development of a Natural Language Processing (NLP) extraction pipeline system, which accepts scanned images of operative and pathology reports. The system uses a combination of rule-based and transfer learning methods to extract numeric encodings from text. We also developed visualization tools to compare the manual and automated extractions. The code for this paper was made available on GitHub. RESULTS: A test set of 50 operative and 50 pathology reports were used to evaluate the extraction accuracies of the NLP pipeline. Gold standard, defined as manual extraction by expert reviewers, yielded accuracies of 90.5% for operative reports and 96.0% for pathology reports, while the NLP system achieved overall 91.9% (operative) and 95.4% (pathology) accuracy. The pipeline successfully extracted outcomes data pertinent to breast cancer tumor characteristics (e.g. presence of invasive carcinoma, size, histologic type), prognostic factors (e.g. number of lymph nodes with micro-metastases and macro-metastases, pathologic stage), and treatment-related variables (e.g. margins, neo-adjuvant treatment, surgical indication) with high accuracy. Out of the 48 variables across operative and pathology codebooks, NLP yielded 43 variables with F-scores of at least 0.90; in comparison, a trained human annotator yielded 44 variables with F-scores of at least 0.90. CONCLUSIONS: The NLP system achieves near-human-level accuracy in both operative and pathology reports using a minimal curated dataset. This system uniquely provides a robust solution for transparent, adaptable, and scalable automation of data extraction from patient health records. It may serve to advance breast cancer clinical research by facilitating collection of vast amounts of valuable health data at a population level.

Chronic pain in breast cancer patients post mastectomy with alloplastic reconstruction: A scoping review.

INTRODUCTION: Women diagnosed with breast cancer are receiving mastectomy with implant-based reconstruction at an increasing rate. Chronic post-surgical pain can be a major concern for these patients. This review sought to address the knowledge gap on the prevalence, severity and characteristics of chronic pain in this population. METHODS: A scoping review was conducted using the Arksey and O'Malley framework. Five databases were searched using keywords. Two independent reviewers performed selection and data extraction of studies that met inclusion criteria. RESULTS: Seventeen studies were included in this review. Ten studies reported prevalence of chronic pain which ranged from 7.3%-90.9% with pooled prevalence of 26.3%. Nine studies reported severity of chronic pain using various scales and methodology; most patients' pain was not severe. Risk factors for chronic pain included axillary dissection, lack of perioperative local anaesthetic, younger age and use of a tissue expander. No studies reported on possible correlation between ethnicity and pain. Eleven different assessment tools were used to measure pain. CONCLUSION: Chronic pain following post-mastectomy implant-based breast reconstruction is prevalent, associated with specific risk factors and poorly characterised. There is a need to investigate and evaluate chronic pain in this population using validated breast cancer specific pain assessment tools.

Truncal-based perforator flaps for autologous breast reconstruction: A review of 975 flaps and their clinical application.

BACKGROUND: When autologous breast reconstruction is desired and deep inferior epigastric artery perforator (DIEP) flap is inadequate or unavailable, other perforator flaps in the truncal region should not be disregarded. This study aimed to review all truncal-based perforator flaps used for autologous breast reconstruction to identify clinical indications and outcomes of alternate perforator flaps. METHODS: From 2013 to 2018, patients undergoing truncal-based perforator flap breast reconstruction were reviewed and data recorded for; indications, pre-operative and intra-operative treatment decisions, flap failures, take-backs, and revisions. Compared to the gold standard of the DIEP flap, alternate truncal-based flaps were evaluated for their reconstructive merit and application. RESULTS: A total of 975 perforator flaps were harvested circumferentially around the lower trunk. As an alternative or adjunct to the DIEP flap (n = 633, 65%), perforator flaps were harvested based on the superficial inferior epigastric, the deep and superficial circumflex iliac arteries, the intercostal, and lumbar arteries (n = 342, 35%). Overlapping vascular territories facilitate the safe harvest of these alternate flaps with 0.8% of flaps requiring take back (n = 8) and 0.2% flap failure rate (n = 2). There was no difference in peri-operative outcomes between anterior abdominal and alternate truncal-based flaps (p > .05). CONCLUSIONS: Circumferential harvest of alternate truncal flaps is an appropriate option for autologous reconstruction with comparable peri-operative and long-term outcomes as compared to flaps from the anterior abdomen.

Management of patients requiring reconstructive breast surgery during the COVID-19 pandemic: recommendations from the BC Regional Breast Reconstruction Network.

Summary: The COVID-19 pandemic has caused unprecedented challenges in health care, threatening access and delivery of medical services across all sectors. Patients with breast cancer desiring breast reconstruction require timely interdisciplinary care; resource limitations threaten access to this elective reconstructive element of cancer care. An expert panel was convened to identify challenges, recommend preliminary solutions, and identify important future directions in anticipation of prolonged restrictions. This paper presents consensus recommendations for care of breast cancer reconstruction patients during the pandemic based on expert opinion from the BC Breast Reconstruction Network.

Development of the Submental Nasal Appearance Scale for the Assessment of Repaired Unilateral Complete Cleft Lip: A Pilot Study.

OBJECTIVE: To develop the "Submental Nasal Appearance Scale" (SNAS), which is an easy-to-use objectified tool to represent a cleft surgeon's standard for assessment of the nasal appearance from the submental perspective. DESIGN: Eighty-five photographs of patients with unilateral complete cleft lip and palate were selected and cropped, displaying the submental view. Sixty-one photographs were used to develop 5 sets of reference photographs. Three cleft surgeons graded 24 photographs with these sets and subjectively graded the overall nasal appearance as well. Internal agreement for both methods was calculated, as well as correlation between them. The SNAS was created, by only using the combination of sets that showed the highest reliability and correlation. SETTING: Boston Children's Hospital, Boston, Massachusetts. PATIENTS: Six- to 9-year-old patients with unilateral complete cleft lip and palate. RESULTS: The intrarater and interrater reliability was 0.84 and 0.79, respectively, for the SNAS and 0.76 and 0.62, respectively, for the overall appearance assessment. The correlation was 0.74 between the methods. CONCLUSIONS: The SNAS is a reliable tool that reflects a cleft surgeon's standard and could be used independently or in combination with existing rating scales using the frontal and/or lateral view, for assessment after cleft lip repair.

An Algorithm for Managing Intraosseous Vascular Anomalies of the Craniofacial Skeleton.

BACKGROUND: Intraosseous vascular anomalies (IOVA) are rare in the craniofacial skeleton and present a diagnostic and therapeutic challenge. This study aims to describe the clinical management based on a large case series. METHODS: A retrospective chart review was performed and 9 IOVA were identified over a 15-year period. Data on demographics, diagnostic features, clinical management, and outcomes were reviewed. RESULTS: Five frontal bone IOVA and 4 orbital IOVA were identified. The postoperative follow-up ranged from 4 months to 4 years. All 9 lesions were diagnosed with computed tomography (CT) imaging. Magnetic resonance imaging (MRI) was used to delineate soft tissue involvement in 2 patients presenting with oculo-orbital dystopia and ophthalmoplegia. En bloc excision was performed in all patients. Preoperative interventional embolization was critical in the successful resection of an orbital IOVA following 2 previously failed attempts that were aborted secondary to hemorrhage. Intraoperative 3-dimensional stereotactic navigation was used for the accurate en bloc excision of a frontal IOVA to prevent injury to the frontal sinus. Reconstruction of esthetic and functional deformities was successfully accomplished. CONCLUSION: The diagnosis of IOVA relies primarily on clinical assessment and CT imaging. Further interpretation of the involvement of periorbital, facial, and intracranial soft tissue is best defined by MRI. Multidisciplinary care with interventional radiology and neurosurgery must be considered for ensuring the safe and adequate en bloc excision of craniofacial IOVA.

Cleft Lip and Palate in CHARGE Syndrome: Phenotypic Features That Influence Management.

OBJECTIVE: Infants with syndromic cleft lip and/or cleft palate (CL/P) often require more complex care than their nonsyndromic counterparts. Our purpose was to (1) determine the prevalence of CL/P in patients with CHARGE syndrome and (2) highlight factors that affect management in this subset of children. DESIGN: This is a retrospective review from 1998 to 2016. PATIENTS: Patients with CHARGE syndrome were diagnosed clinically and genetically. MAIN OUTCOMES MEASURES: Prevalence of CL/P was determined and clinical details tabulated: phenotypic anomalies, cleft types, operative treatment, and results of repair. RESULTS: CHARGE syndrome was confirmed in 44 patients: 11 (25%) had cleft lip and palate and 1 had cleft palate only. Surgical treatment followed our usual protocols. Two patients with cardiac anomalies had prolonged recovery following surgical correction, necessitating palatal closure prior to nasolabial repair. One of these patients was too old for dentofacial orthopedics and underwent combined premaxillary setback and palatoplasty, prior to labial closure. Velopharyngeal insufficiency was frequent (n = 3/7). All patients had feeding difficulty and required a gastrostomy tube. All patients had neurosensory hearing loss; anomalies of the semicircular canals were frequent (n = 3/4). External auricular anomalies, colobomas, and cardiovascular anomalies were also common (n = 8/11). Other associated anomalies were choanal atresia (n = 4/11) and tracheoesophageal fistula (n = 2/11). CONCLUSIONS: CHARGE syndrome is an under-recognized genetic cause of cleft lip and palate. Hearing loss and speech and feeding difficulties often occur in these infants. Diagnosis can be delayed if the child presents with covert phenotypic features, such as chorioretinal colobomas, semicircular canal hypoplasia, and unilateral choanal atresia.

Three-Dimensional Imaging and Breast Measurements: How Predictable Are We?

BACKGROUND: Outcomes in aesthetic breast surgery are dependent on preoperative breast measurements. The accuracy of 3-dimensional (3D) imaging in measuring critical landmarks in augmentation mammaplasty surgery has not been described. OBJECTIVES: We aimed to determine the predictability of 3D imaging compared to direct measurements. METHODS: Two raters measured the breasts of 28 women using four anthropometric (direct) measurements: sternal notch to nipple distance (Sn-N), nipple to midline (N-M), nipple to inframammary-fold distance under maximal stretch (N-IMF), and base width (BW). Measurements (indirect) were also obtained using 3D imaging. Statistical analysis was completed with Bland-Altman plots. RESULTS: Each rater collected 56 data points for each of the four measurements. This resulted in 224 data points per rater. The Sn-N measurement had a 0.05 cm (SD, 0.65) difference in the mean values obtained between direct and indirect measurements. N-M had a mean difference of 0.20 cm (SD, 0.62). The mean difference for BW was 1.26 cm (SD, 0.69 cm), and N-IMF showed a mean difference of 1.22 cm (SD, 0.74 cm). Three-dimensional imaging overestimated Sn-N, N-M, and BW, while it underestimated N-IMF. CONCLUSIONS: Three-dimensional imaging has good utility and is most accurate for Sn-N and N-M measurements, which require frontal imaging of a standing patient. BW and N-IMF are less accurate due to obscured landmarks on frontal imaging. The medial and lateral aspects of the breast may be obscured when measuring BW on 3D imaging, which may explain this difference. N-IMF is a dynamic measurement, and as a result, 3D imaging has limited ability to measure this distance accurately.

Drainless Abdominoplasty Using Barbed Progressive Tension Sutures.

We describe our current technique of drainless abdominoplasty using barbed progressive tension sutures. The perioperative management and detailed steps of procedure are outlined, including indications for concomitantly performing liposuction and repair of diastasis of the rectus abdominis muscles. This approach reliably improves abdominal contour, minimizes complications, and is straightforward to learn and perform.

The Reliability of Anthropometric Measurements Used Preoperatively in Aesthetic Breast Surgery.

BACKGROUND: Patient outcomes in aesthetic breast surgery are highly dependent on breast measurements used in preoperative planning. OBJECTIVES: The purpose of this study is to determine the reliability of anthropometric breast measurements. METHODS: Four raters measured 28 women using 7 measurements: sternal notch to nipple distance (Sn-N), nipple to midline (N-M), nipple to inframammary-fold distance under maximal stretch (N-IMF), breast base width (BW), soft tissue pinch thickness of the upper pole (STPT:UP), STPT at the inframammary fold (STPT:IMF), and anterior pull skin stretch (APSS). Reliability was assessed using intra-class correlation coefficients (ICCs). RESULTS: Inter-rater reliability was excellent for Sn-N, N-M, and BW (ICC = 0.94, 0.90, and 0.76, respectively) and was good for N-IMF (ICC = 0.70). The STPT:UP, STPT:IMF, and APSS measurements were not reliable between raters (ICC < 0.2). Intra-rater reliability was excellent for Sn-N, N-M, and BW for all raters (all ICC > 0.75). The N-IMF intra-rater reliability was excellent in senior raters (ICC > 0.75) and good in junior raters (ICC > 0.6). The STPT:UP, STPT:IMF, and APSS measurements showed fair or poor reliability for most raters (ICC < 0.6). CONCLUSIONS: The Sn-N, N-M, and BW measurements are very reliable. Dynamic measurements including APSS, STPT:UP, and STUP:IMF are unreliable. N-IMF is the only reliable dynamic measurement, and its reliability improves with increasing clinical experience. The variable reliability of preoperative measurements must be considered in the planning of aesthetic breast surgery. LEVEL OF EVIDENCE: 4 Diagnostic.

Cardiothoracic ratio on chest radiograph in pediatric heart disease: How does it correlate with heart volumes at magnetic resonance imaging?

BACKGROUND: The cardiothoracic ratio by chest radiograph is widely used as a marker of cardiac size. OBJECTIVE: The purpose of this study is to correlate cardiothoracic ratio and cardiac volumes as measured by cardiovascular magnetic resonance (MR) in common structural and myopathic heart disease with increased cardiac size due to volume overload or hypertrophy. MATERIAL AND METHODS: A retrospective single center study was performed in all patients between 2007 and 2013 with repaired tetralogy of Fallot (TOF), aortic regurgitation, isolated left-to-right shunt and hypertrophic cardiomyopathy (HCM) who underwent cardiovascular MR and chest radiograph within 6 months of each other. Cardiothoracic ratios by chest radiograph (frontal and lateral) were compared to cardiac volumes (indexed for body surface area) by cardiovascular MR. RESULTS: One hundred twenty-seven patients (mean age: 11.2 ± 5.5 years) were included in this study (76 with TOF, 23 with isolated left-to-right shunt, 16 with aortic regurgitation and 12 with HCM). Frontal cardiothoracic ratio of all groups correlated with indexed right ventricular (RV) end-diastolic volume (EDVI) (r = 0.40, P < 0.01) and indexed total heart volume (THVI) (r = 0.27, P < 0.01). In TOF patients, frontal cardiothoracic ratio correlated with RVEDVI (r = 0.34, P < 0.01; coefficient of variation = 27.6%), indexed RV end-systolic volume (ESVI) (r = 0.44, P < 0.01; coefficient of variation = 33.3%) and THVI (r = 0.35, P < 0.01; coefficient of variation = 19.6%), although RV volumes and THVI showed widespread variation given the high coefficients of variation. In patients with aortic regurgitation, frontal cardiothoracic ratio correlated with left ventricular (LV) EDVI (r = 0.50, P = 0.047), but not with THVI and aortic regurgitant fraction, and widespread variation for LV EDVI (coefficient of variation = 19.2%), LV ESVI (coefficient of variation = 32.5%) and THVI (coefficient of variation = 13.6%) was also observed. Frontal cardiothoracic ratio was not correlated with cardiac volumes or mass in patients with a left-to-right shunt or HCM. Lateral cardiothoracic ratio showed no correlation with any cardiac volume in all four groups. CONCLUSION: Although increased cardiothoracic ratio on frontal chest radiograph is associated with increased biventricular volumes in patients with pulmonary and aortic regurgitation, significant variation in ventricular volumes and total heart volume for any given frontal cardiothoracic ratio limits the use of cardiothoracic ratio in monitoring the individual patient's heart size. Frontal cardiothoracic ratio did not correlate with cardiac chamber volumes in patients with a left-to-right shunt or HCM and lateral cardiothoracic ratio offered no additional value for cardiac size assessment.

Optimization of Cranio-Orbital Remodeling: Application of a Mathematical Model.

Cranio-orbital remodeling aims to correct the dysmorphic skull associated with craniosynostosis. Traditionally, the skull is reconstructed into a shape that is subjectively normal according to the surgeon's perception. We present a novel technique using a mathematical algorithm to define the optimal location for bony osteotomies and to objectively reshape the fronto-orbital bar into an ideal normal skull contour. Using pre-operative computed tomography images, the abnormal skull contour at the frontal-orbital region was obtained for infants planned to undergo cranio-orbital remodeling. The ideal skull shape was derived from an age- and sex-matched normative skull library. For each patient, the mathematical technique of dynamic programming (DP) was applied to compare the abnormal and ideal skull shapes. The DP algorithm identifies the optimal location of osteotomy sites and calculates the objective difference in surface area remaining between the normative and dysmorphic skull shape for each solution applied. By selecting the optimal solution with minimal objective difference, the surgeon is guided to reproducibly recreate the normal skull contour with defined osteotomies. The DP algorithm was applied in 13 cases of cranio-orbital remodeling. Five female and 8 male infants with a mean age of 11 months were treated for craniosynostosis classified as metopic (n = 7), unicoronal (n = 4), or bicoronal (n = 2). The mean OR time was 190.2  min (SD 33.6), mean estimated blood loss 244  cc (SD 147.6), and 10 infants required blood transfusions. Compared with a historical crania-orbital remodeling group treated without application of the algorithm, there was no significant difference in OR time, estimated blood loss, or transfusion rate. This novel technique enables the craniofacial surgeon to objectively reshape the fronto-orbital bar and reproducibly reconstruct a skull shape resembling that of normal infants.

Implant Texture and Capsular Contracture: A Review of Cellular and Molecular Pathways.

Background: Capsular contracture (CC) is a leading cause of morbidity in implant-based breast surgery. Implant surface texture has been implicated in CC development, yet its etiopathogenesis remains unclear. We conducted a systematic review to determine the influence of implant surface texture on cellular and molecular mechanisms involved in the etiopathogenesis of CC. Methods: A systematic review of the MEDLINE, Embase, Web of Science, and Scopus databases was completed to examine the influence of implant texture on cellular and molecular pathways leading to CC. Excluded articles were reviews and those examining solely the clinical presentation of CC. Results: Development of CC includes prolonged inflammation, increased myofibroblast density, parallel arrangement of collagen fibers, and biofilm formation. When compared with textured implants, smooth implants are associated with reduction in parallel collagen, capsule thickness, and sheer frictional force. Microtextured implants trigger a reduced macrophage response and decreased fibroblast activation as compared with smooth and macrotextured surfaces. Bacterial counts on microtextured and smooth surfaces are significantly lower than that of macrotextured surfaces. Both micro- and macrotextured implants have increased matrix metalloproteinases and activation of tumor necrosis factor α pathway, with increased activation of the transforming growth factor ß1 pathway relative to smooth implants. Conclusions: Implant surface texture alters the cellular and molecular mechanisms in the chronic inflammatory process leading to CC. Given the complex biological system of cellular and molecular events in CC, a mathematical model integrating these influences may be optimal to deduce the etiopathogenesis.

Machine Learning to Predict the Need for Postmastectomy Radiotherapy after Immediate Breast Reconstruction.

Background: Post mastectomy radiotherapy (PMRT) is an independent predictor of reconstructive complications. PMRT may alter the timing and type of reconstruction recommended. This study aimed to create a machine learning model to predict the probability of requiring PMRT after immediate breast reconstruction (IBR). Methods: In this retrospective study, breast cancer patients who underwent IBR from January 2017 to December 2020 were reviewed and data were collected on 81 preoperative characteristics. Primary outcome was recommendation for PMRT. Four algorithms were compared to maximize performance and clinical utility: logistic regression, elastic net (EN), logistic lasso, and random forest (RF). The cohort was split into a development dataset (75% of cohort for training-validation) and 25% used for the test set. Model performance was evaluated using area under the receiver operating characteristic curve (AUC), precision-recall curves, and calibration plots. Results: In a total of 800 patients, 325 (40.6%) patients were recommended to undergo PMRT. With the training-validation dataset (n = 600), model performance was logistic regression 0.73 AUC [95% confidence interval (CI) 0.65-0.80]; RF 0.77 AUC (95% CI, 0.74-0.81); EN 0.77 AUC (95% CI, 0.73-0.81); logistic lasso 0.76 AUC (95% CI, 0.72-0.80). Without significantly sacrificing performance, 81 predictive factors were reduced to 12 for prediction with the EN method. With the test dataset (n = 200), performance of the EN prediction model was confirmed [0.794 AUC (95% CI, 0.730-0.858)]. Conclusion: A parsimonious accurate machine learning model for predicting PMRT after IBR was developed, tested, and translated into a clinically applicable online calculator for providers and patients.

The Best of Chest Wall Reconstruction: Principles and Clinical Application for Complex Oncologic and Sternal Defects.

LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Appraise and evaluate risk factors for respiratory compromise following oncologic resection. 2. Outline and apply an algorithmic approach to reconstruction of the chest wall based on defect composition, size, and characteristics of surrounding tissue. 3. Recognize and evaluate indications for and types of skeletal stabilization of the chest wall. 4. Critically consider, compare, and select pedicled and free flaps for chest wall reconstruction that do not impair residual respiratory function or skeletal stability. SUMMARY: Chest wall reconstruction restores respiratory function, provides protection for underlying viscera, and supports the shoulder girdle. Common indications for chest wall reconstruction include neoplasms, trauma, infectious processes, and congenital defects. Loss of chest wall integrity can result in respiratory and cardiac compromise and upper extremity instability. Advances in reconstructive techniques have expanded the resectability of large complex oncologic tumors by safely and reliably restoring chest wall integrity in an immediate fashion with minimal or no secondary deficits. The purpose of this article is to provide the reader with current evidenced-based knowledge to optimize care of patients requiring chest wall reconstruction. This article discusses the evaluation and management of oncologic chest wall defects, reviews controversial considerations in chest wall reconstruction, and provides an algorithm for the reconstruction of complex chest wall defects. Respiratory preservation, semirigid stabilization, and longevity are key when reconstructing chest wall defects.