Diagnostic accuracy of a three-protein signature in women with suspicious breast lesions: a multicenter prospective trial.

BACKGROUND: Mammography screening has been proven to detect breast cancer at an early stage and reduce mortality; however, it has low accuracy in young women or women with dense breasts. Blood-based diagnostic tools may overcome the limitations of mammography. This study assessed the diagnostic performance of a three-protein signature in patients with suspicious breast lesions. FINDINGS: This trial (MAST; KCT0004847) was a prospective multicenter observational trial. Three-protein signature values were obtained using serum and plasma from women with suspicious lesions for breast malignancy before tumor biopsy. Additionally, blood samples from women who underwent clear or benign mammography were collected for the assays. Among 642 participants, the sensitivity, specificity, and overall accuracy values of the three-protein signature were 74.4%, 66.9%, and 70.6%, respectively, and the concordance index was 0.698 (95% CI 0.656, 0.739). The diagnostic performance was not affected by the demographic features, clinicopathologic characteristics, and co-morbidities of the participants. CONCLUSIONS: The present trial showed an accuracy of 70.6% for the three-protein signature. Considering the value of blood-based biomarkers for the early detection of breast malignancies, further evaluation of this proteomic assay is warranted in larger, population-level trials. This Multi-protein Assessment using Serum to deTermine breast lesion malignancy (MAST) was registered at the Clinical Research Information Service of Korea with the identification number of KCT0004847 ( https://cris.nih.go.kr ).

Recurrence is Not Associated with Margin Status in Phyllodes Tumor.

BACKGROUND: Phyllodes tumor (PT) is a rare fibroepithelial neoplasm of the breast. The proper extent of resection is still under debate. This study aimed to investigate the optimal surgical margin to prevent recurrence after surgery for PT and to evaluate risk factors for local recurrence (LR). METHODS: Retrospective analysis of a prospective cohort database was performed. Patients who underwent curative surgery for PT at Seoul National University Bundang Hospital between July 2003 and February 2022 were reviewed. RESULTS: Of the 439 patients included, 285 were benign, 129 were borderline, and 25 were malignant. There was no statistically significant difference in 5-year disease-free survival (DFS) between margin-negative and margin-involved patients (87.3% vs. 85.1%, p = 0.081). When patients were classified into groups, according to margin status, as conventional (≥ 1 cm from tumor), close (< 1 cm from tumor), or involved, 5-year DFS rates were also similar (100% vs. 86.9% vs. 85.1%, p = 0.170). In subgroup analysis for different histologic grades, 5-year DFS was not affected by margin involvement. In univariate analysis, large tumor size (> 5 cm; hazard ratio [HR] 2.857, p = 0.028) and infiltrative tumor border (HR 3.096, p = 0.012) were independent risk factors for LR. Further multivariate analysis found both factors to be prognostic. CONCLUSIONS: Recurrence was not significantly influenced by margin status in all histological grades. In benign and borderline tumors, local excision without wide surgical margins could be sufficient, and watchful waiting could be an option for patients with positive margins after initial surgery.

The Potential Predictors in Chemotherapy Sensitivity.

Monitoring of patient and tumor during chemotherapy is important to determine whether the chemotherapy is effective to the patient. Variants affect drug enzyme activities and altered enzyme activities can be potential predictors for chemotherapeutic agents including cyclophosphamide and paclitaxel. Response to chemotherapy is primarily based on somatic mutations but germline variants may predict cancer cell sensitivity to chemotherapeutic agents. Furthermore, patient's genetic variation of immune system was reported to be associated with drug response and toxicity. Recently, the somaric and germilne genomic variation influences the pharmacokinetics of chemotherapy and these variation can be biomarkers for chemotherapy.

External validation and modification of nomogram for predicting positive resection margins before breast conserving surgery.

PURPOSE: A positive resection margin after breast conserving surgery (BCS) is the most important risk factor for tumor recurrence. In 2012, Seoul National University Hospital (SNUH) breast surgery team developed a nomogram for predicting positive resection margins before BCS to provide individual surgical plans that could reduce local recurrence without increasing re-excision rates. The purpose of this study was to validate this nomogram using an external cohort and to test if addition of surgeon-related factor could improve its use as a predictive model. METHODS: A total of 419 patients with breast cancer who underwent BCS from January to December 2018 were retrospectively reviewed. Using the SNUH BCS nomogram, risk score for positive resection margins was calculated for 343 patients. The predictive accuracy of the nomogram was assessed, and multivariable logistic regression analyses were performed to evaluate the nomogram's predictive variables. RESULTS: The positive resection margin rate of the current external validation cohort was 13.5% (46 out of 343), compared to 14.6% (151 out of 1034) of the original study. The discrimination power of the SNUH BCS nomogram as measure by area under the receiver operating characteristics curve (AUC) was 0.656 [95% confidence interval (CI) 0.576-0.735]. This result is lower than expected value of 0.823 [95% CI 0.785-0.862], the AUC of the original study. Multivariable logistic regression analysis showed that, among the five nomogram variables, presence of tumor size discrepancy greater than 0.5 cm between MRI and ultrasonography (OR 2.445, p = 0.019) and presence of ductal carcinoma in situ on needle biopsy (OR 2.066, p = 0.048) were significantly associated with positive resection margins. Finally, the nomogram score was re-calculated by adding each surgeon's resection margin positive rate as odds ratio and the AUC was increased to 0.733. CONCLUSIONS: Validation of the SNUH BCS nomogram was not successful in the current study as much as its original publication. However, we could improve its predictive power by including surgeon-related factor. Before applying a published nomogram as a preoperative predictive model, we suggest each institution to validate the model and adjust it with surgeon-related factor. Addition of new factors to currently available nomograms holds promise for improving its applicability for breast cancer patients at the actual clinical level.

Risk factors for locoregional disease recurrence after breast-conserving therapy in patients with breast cancer treated with neoadjuvant chemotherapy: An international collaboration and individual patient meta-analysis.

BACKGROUND: Several studies have reported a high risk of local disease recurrence (LR) and locoregional disease recurrence (LRR) in patients with breast cancer after neoadjuvant chemotherapy (NCT) and breast-conserving therapy (BCT). The objective of the current study was to identify potential risk factors for LR and LRR after NCT and BCT. METHODS: Individual patient data sets from 9 studies were pooled. The outcomes of interest were the occurrence of LR and/or LRR. A 1-stage meta-analytic approach was used. Cox proportional hazards regression models were applied to identify factors that were predictive of LR and LRR, respectively. RESULTS: A total of 9 studies (4125 patients) provided their data sets. The 10-year LR rate was 6.5%, whereas the 10-year LRR rate was 10.3%. Four factors were found to be associated with a higher risk of LR: 1) estrogen receptor-negative disease; 2) cN + disease; 3) a lack of pathologic complete response in axilla (pN0); and 4) pN2 to pN3 disease. The predictive score for LR determined 3 risk groups: a low-risk, intermediate-risk, and high-risk group with 10-year LR rates of 4.0%, 7.9%, and 20.4%, respectively. Two additional factors were found to be associated with an increased risk of LRR: cT3 to cT4 disease and a lack of pathologic complete response in the breast. The predictive score for LRR determined 3 risk groups; a low-risk, intermediate-risk, and high-risk group with 10-year LRR rates of 3.2%, 10.1%, and 24.1%, respectively. CONCLUSIONS: BCT after NCT appears to be an oncologically safe procedure for a large percentage of patients with breast cancer. Two easy-to-use clinical scores were developed that can help clinicians to identify patients at higher risk of LR and LRR after NCT and BCT and individualize the postoperative treatment plan and follow-up. Cancer 2018;124:2923-30. © 2018 American Cancer Society.

An objective nodal staging system for breast cancer patients undergoing neoadjuvant systemic treatment.

BACKGROUND: In this study, we aimed to develop an objective staging system to determine the degree of nodal metastasis in breast cancer patients undergoing neoadjuvant systemic treatment (NST). METHODS: We reviewed the pretreatment computed tomography (CT) images of 392 breast cancer patients who received NST. The association between the patterns of the enlarged regional lymph nodes and treatment outcome was analyzed. RESULTS: In the development cohort of 260 patients, 88 (33.8%) patients experienced tumor recurrence and had a significantly higher number of enlarged lymph nodes on the pretreatment CT compared to patients with no recurrence. When patients were classified according to the numbers and locations of enlarged lymph nodes on pretreatment CT, the number of lymph nodes larger than 1 cm was most significantly associated with tumor recurrence. The accuracy of the CT-based nodal staging system was validated in an independent cohort of 132 patients. The presence of the enlarged supraclavicular nodes was associated with worse outcome, but the effect seemed to originate from the accompanied extensive axillary nodal burden. The prognostic effect of the objectively measured axillary nodal metastasis was more pronounced in hormone receptor-negative tumors. CONCLUSIONS: We have developed and validated an objective method of nodal staging in breast cancer patients who undergo NST based on the number of enlarged axillary lymph nodes. Our system can improve the current subjective approach, which uses physical examination alone.

Trends in the Use of Chemotherapy before and after Radical Cystectomy in Patients with Muscle-invasive Bladder Cancer in Korea.

We investigated trends in perioperative chemotherapy use, and determined factors associated with neoadjuvant chemotherapy (NAC) and adjuvant chemotherapy (AC) use in Korean patients with muscle-invasive bladder cancer (MIBC). We recruited 1,324 patients who had MIBC without nodal invasion or metastases and had undergone radical cystectomies (RC) between 2003 and 2013. The study's cut-off time for AC was three months after surgery, and the study's timespan was divided into three periods based on NAC use, namely, 2003-2005, 2006-2009, and 2010-2013. Complete remission was defined as histologically confirmed T0N0M0 after RC. NAC and AC were administered to 7.3% and 18.1% of the patients, respectively. The median time interval between completing NAC and undergoing RC was 32 days and the mean number of cycles was 3.2. The median time interval between RC and AC was 43 days and the mean number of cycles was 4.1. Gemcitabine and cisplatin were most frequently used in combination for NAC (49.0%) and AC (74.9%). NAC use increased significantly from 4.6% between 2003 and 2005 to 8.4% between 2010 and 2013 (P < 0.05), but AC use did not increase. Only 1.9% of patients received NAC and AC. Complete remission after NAC was achieved in 12 patients (12.5%). Multivariable modeling revealed that an advanced age, the earliest time period analyzed, and clinical tumor stage ≤ cT2 bladder cancer were negatively associated with NAC use (P < 0.05). While NAC use has slowly increased over time, it remains an underutilized therapeutic approach in Korean clinical practice.

Concordance of HER2 status between core needle biopsy and surgical resection specimens of breast cancer: an analysis focusing on the HER2-low status.

BACKGROUND: Human epidermal growth factor receptor 2 (HER2)-low status has recently gained attention because of the potential therapeutic benefits of antibody-drug conjugates (ADCs) in breast cancer patients. We aimed to investigate the concordance of HER2 status between core needle biopsy (CNB) and subsequent surgical resection specimens focusing on the HER2-low status. METHODS: This retrospective study was conducted in 1,387 patients with invasive breast cancer whose HER2 status was evaluated in both CNB and surgical resection specimens. The discordance rates between CNB and surgical resection specimens and the clinicopathological features associated with HER2 status discordance were analyzed. RESULTS: The overall concordance rates of HER2 status between CNB and surgical resection specimens were 99.0% (κ = 0.925) for two-group classification (negative vs. positive) and 78.5% (κ = 0.587) for three-group classification (zero vs. low vs. positive). The largest discordance occurred in CNB-HER2-zero cases with 42.8% of them reclassified as HER2-low in surgical resection. HER2 discordance was associated with lower histologic grade, tumor multiplicity, and luminal A subtype. In multivariate analysis, tumor multiplicity and estrogen receptor (ER) positivity were independent predictive factors for HER2-zero to low conversion. CONCLUSIONS: Incorporation of HER2-low category in HER2 status interpretation reduces the concordance rate between CNB and surgical resection specimens. Tumor multiplicity and ER positivity are predictive factors for conversion from HER2-zero to HER2-low status. Therefore, HER2 status should be re-evaluated in resection specimens when considering ADCs in tumors exhibiting multiplicity and ER positivity.

Comparative profiling by data-independent acquisition mass spectrometry reveals featured plasma proteins in breast cancer: a pilot study.

Purpose: Breast cancer is known to be influenced by genetic and environmental factors, and several susceptibility genes have been discovered. Still, the majority of genetic contributors remain unknown. We aimed to analyze the plasma proteome of breast cancer patients in comparison to healthy individuals to identify differences in protein expression profiles and discover novel biomarkers. Methods: This pilot study was conducted using bioresources from Seoul National University Bundang Hospital's Human Bioresource Center. Serum samples from 10 breast cancer patients and 10 healthy controls were obtained. Liquid chromatography-mass spectrometry analysis was performed to identify differentially expressed proteins. Results: We identified 891 proteins; 805 were expressed in the breast cancer group and 882 in the control group. Gene set enrichment and differential expression analysis identified 30 upregulated and 100 downregulated proteins in breast cancer. Among these, 10 proteins were selected as potential biomarkers. Three proteins were upregulated in breast cancer patients, including cluster of differentiation 44, eukaryotic translation initiation factor 2-α kinase 3, and fibronectin 1. Seven proteins downregulated in breast cancer patients were also selected: glyceraldehyde-3-phosphate dehydrogenase, α-enolase, heat shock protein member 8, integrin-linked kinase, tissue inhibitor of metalloproteinases-1, vasodilator-stimulated phosphoprotein, and 14-3-3 protein gamma. All proteins had been previously reported to be related to tumor development and progression. Conclusion: The findings suggest that plasma proteome profiling can reveal potential diagnostic biomarkers for breast cancer and may contribute to early detection and personalized treatment strategies. A further validation study with a larger sample cohort of breast cancer patients is planned.

Automated Versus Handheld Breast Ultrasound for Evaluating Axillary Lymph Nodes in Patients With Breast Cancer.

OBJECTIVE: Automated breast ultrasound (ABUS) is a relevant imaging technique for early breast cancer diagnosis and is increasingly being used as a supplementary tool for mammography. This study compared the performance of ABUS and handheld ultrasound (HHUS) in detecting and characterizing the axillary lymph nodes (LNs) in patients with breast cancer. MATERIALS AND METHODS: We retrospectively reviewed the medical records of women with recently diagnosed early breast cancer (≤ T2) who underwent both ABUS and HHUS examinations for axilla (September 2017-May 2018). ABUS and HHUS findings were compared using pathological outcomes as reference standards. Diagnostic performance in predicting any axillary LN metastasis and heavy nodal-burden metastases (i.e., ≥ 3 LNs) was evaluated. The ABUS-HHUS agreement for visibility and US findings was calculated. RESULTS: The study included 377 women (53.1 ± 11.1 years). Among 385 breast cancers in 377 patients, 101 had axillary LN metastases and 30 had heavy nodal burden metastases. ABUS identified benign-looking or suspicious axillary LNs (average, 1.4 ± 0.8) in 246 axillae (63.9%, 246/385). According to the per-breast analysis, the sensitivity, specificity, positive and negative predictive values, and accuracy of ABUS in predicting axillary LN metastases were 43.6% (44/101), 95.1% (270/284), 75.9% (44/58), 82.6% (270/327), and 81.6% (314/385), respectively. The corresponding results for HHUS were 41.6% (42/101), 95.1% (270/284), 75.0% (42/56), 82.1% (270/329), and 81.0% (312/385), respectively, which were not significantly different from those of ABUS (P ≥ 0.53). The performance results for heavy nodal-burden metastases were 70.0% (21/30), 89.6% (318/355), 36.2% (21/58), 97.3% (318/327), and 88.1% (339/385), respectively, for ABUS and 66.7% (20/30), 89.9% (319/355), 35.7% (20/56), 97.0% (319/329), and 88.1% (339/385), respectively, for HHUS, also not showing significant difference (P ≥ 0.57). The ABUS-HHUS agreement was 95.9% (236/246; Cohen's kappa = 0.883). CONCLUSION: Although ABUS showed limited sensitivity in diagnosing axillary LN metastasis in early breast cancer, it was still useful as the performance was comparable to that of HHUS.

Omission of Breast Surgery in Predicted Pathologic Complete Response after Neoadjuvant Systemic Therapy: A Multicenter, Single-Arm, Non-inferiority Trial.

PURPOSE: Advances in chemotherapeutic and targeted agents have increased pathologic complete response (pCR) rates after neoadjuvant systemic therapy (NST). Vacuum-assisted biopsy (VAB) has been suggested to accurately evaluate pCR. This study aims to confirm the non-inferiority of the 5-year disease-free survival of patients who omitted breast surgery when predicted to have a pCR based on breast magnetic resonance imaging (MRI) and VAB after NST, compared with patients with a pCR who had undergone breast surgery in previous studies. METHODS: The Omission of breast surgery for PredicTed pCR patients wIth MRI and vacuum-assisted bIopsy in breaST cancer after neoadjuvant systemic therapy (OPTIMIST) trial is a prospective, multicenter, single-arm, non-inferiority study enrolling in 17 tertiary care hospitals in the Republic of Korea. Eligible patients must have a clip marker placed in the tumor and meet the MRI criteria suggesting complete clinical response (post-NST MRI size ≤ 1 cm and lesion-to-background signal enhancement ratio ≤ 1.6) after NST. Patients will undergo VAB, and breast surgery will be omitted for those with no residual tumor. Axillary surgery can also be omitted if the patient was clinically node-negative before and after NST and met the stringent criteria of MRI size ≤ 0.5 cm. Survival and efficacy outcomes are evaluated over five years. DISCUSSION: This study seeks to establish evidence for the safe omission of breast surgery in exceptional responders to NST while minimizing patient burden. The trial will address concerns about potential undertreatment due to false-negative results and recurrence as well as improved patient-reported quality of life issues from the omission of surgery. Successful completion of this trial may reshape clinical practice for certain breast cancer subtypes and lead to a safe and less invasive approach for selected patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05505357. Registered on August 17, 2022. Clinical Research Information Service Identifier: KCT0007638. Registered on July 25, 2022.

Preoperative serum tissue polypeptide-specific antigen is a valuable prognostic marker in breast cancer.

Tissue polypeptide-specific antigen (TPS), a specific epitope structure of a peptide in serum associated with human cytokeratin 18, is linked to the proliferative activity of tumors. Here, we aimed to identify the association between the preoperative serum TPS level and outcome in breast cancer patients. We assayed preoperative serum TPS levels in 1,477 breast cancer patients treated between June 2000 and December 2006. The TPS level was measured with a one-step solid phase radiometric sandwich assay detecting the M3 epitope on cytokeratin 18 fragments. The cutoff value was 80 U/L. Among the 1,477 breast cancer patients examined, preoperative serum TPS level was elevated (>80 U/L) in 290 patients (19.6%). Age (>45 years), tumor size (>2 cm), nodal metastasis, negative progesterone receptor and human epidermal growth factor receptor 2 were associated with elevated TPS. Evidence of recurrence was observed in 229 patients (15.6%). Elevated TPS was associated with poor disease-free survival (p < 0.001) and overall survival (p < 0.001). In a multivariate analysis using the Cox proportional regression model, elevated TPS was an independent prognostic factor for disease-free survival (p = 0.001) and overall survival (p = 0.026). Furthermore, in subgroup analysis based on molecular subtype, the prognostic effect of preoperative TPS on survival (OS: HR 2.614, p = 0.003; DFS: HR 1.895, p = 0.001) was identified only in the luminal A subtype. Elevated preoperative serum TPS level is associated with poor breast cancer outcomes. Based on these findings, we conclude that preoperative TPS is a valuable biomarker for clinical use in predicting outcomes in breast cancer patients.

Breast-conserving surgery after tumor downstaging by neoadjuvant chemotherapy is oncologically safe for stage III breast cancer patients.

BACKGROUND: We conducted a retrospective study to evaluate the local recurrence (LR) rate depending on the use of neoadjuvant chemotherapy (NCT) and to determine the oncologic safety of breast-conserving surgery (BCS) after NCT by comparing LR between patients treated with BCS and mastectomy in clinical stage III breast cancer patients. PATIENTS AND METHODS: Between 2004 and 2007, 166 patients underwent BCS or mastectomy after NCT (NCT group) and 193 patients underwent surgery first (surgery group) in clinical stage III breast cancer patients. Patients whose tumor size became ≤4 cm after NCT, 57 patients underwent mastectomy (mastectomy group) 39 patients underwent preplanned BCS (preplanned BCS group), and 33 patients underwent downstaged BCS (downstaged BCS group). The recurrence rates between the groups and risk factors for LR were analyzed. RESULTS: The 5-year LR-free survival rates were 93.6 % in the NCT group and 95.9 % in the surgery group (P = 0.108). In the NCT group, the 5-year LR-free survival rates were 96.3 % in the mastectomy group, 94.7 % in the preplanned BCS group and 90.9 % in the downstaged BCS group (P = 0.669). High expression of Ki-67 was a predictor of LR in patients in three groups (Hazard ratio 8.300, P = 0.049). CONCLUSIONS: Our findings suggest that BCS after NCT in clinical stage III patients is oncologically safe in terms of LR if breast tumor size is ≤4 cm after NCT and Ki-67 is a predictor of LR after NCT.

A pilot study evaluating liquid-based fine needle aspiration cytology of breast lesions: a cytomorphological comparison of SurePath® liquid-based preparations and conventional smears.

OBJECTIVE: Fine needle aspiration cytology (FNAC) is recommended by the World Health Organization as a diagnostic method for breast lesions. The morphological interpretation of liquid-based preparations (LBPs) remains a diagnostic challenge due to considerably altered cytomorphology. The aim of the current study was to compare cytomorphological characteristics of SurePath® (SP)-based LBP and conventional smear (CS) in breast FNACs. STUDY DESIGN: The study included 77 benign and 60 malignant breast FNACs obtained by both SP and CS, all with tissue confirmation. Cases analyzed with both preparations were reviewed and compared, focusing on 10 cytomorphological features. RESULTS: SP aspirates demonstrated notable cytomorphological alterations. Among them, a prominent three-dimensional configuration of cell clusters and frequent and conspicuous nucleoli were the most prominent characteristics of SP compared with CS. Overall diagnostic performances were comparable but were slightly lower for SP than CS (diagnostic accuracy of two reviewers; 87.6 and 90.5% for SP vs. 91.2 and 92.7% for CS, respectively). CONCLUSION: Although the reviewer should be aware of distinctive cytomorphological alterations, the SP technique is reliable for the evaluation of breast lesions with the advantage of easy interpretation and a diagnostic accuracy equivalent to CS.

Development of a Breast Cancer Risk Prediction Model Incorporating Polygenic Risk Scores and Nongenetic Risk Factors for Korean Women.

BACKGROUND: To develop a breast cancer prediction model for Korean women using published polygenic risk scores (PRS) combined with nongenetic risk factors (NGRF). METHODS: Thirteen PRS models generated from single or multiple combinations of the Asian and European PRSs were evaluated among 20,434 Korean women. The AUC and increase in OR per SD were compared for each PRS. The PRSs with the highest predictive power were combined with NGRFs; then, an integrated prediction model was established using the Individualized Coherent Absolute Risk Estimation (iCARE) tool. The absolute breast cancer risk was stratified for 18,142 women with available follow-up data. RESULTS: PRS38_ASN+PRS190_EB, a combination of Asian and European PRSs, had the highest AUC (0.621) among PRSs, with an OR per SD increase of 1.45 (95% confidence interval: 1.31-1.61). Compared with the average risk group (35%-65%), women in the top 5% had a 2.5-fold higher risk of breast cancer. Incorporating NGRFs yielded a modest increase in the AUC of women ages >50 years. For PRS38_ASN+PRS190_EB+NGRF, the average absolute risk was 5.06%. The lifetime absolute risk at age 80 years for women in the top 5% was 9.93%, whereas that of women in the lowest 5% was 2.22%. Women at higher risks were more sensitive to NGRF incorporation. CONCLUSIONS: Combined Asian and European PRSs were predictive of breast cancer in Korean women. Our findings support the use of these models for personalized screening and prevention of breast cancer. IMPACT: Our study provides insights into genetic susceptibility and NGRFs for predicting breast cancer in Korean women.

Development and External Validation of a Machine Learning Model to Predict Pathological Complete Response After Neoadjuvant Chemotherapy in Breast Cancer.

PURPOSE: Several predictive models have been developed to predict the pathological complete response (pCR) after neoadjuvant chemotherapy (NAC); however, few are broadly applicable owing to radiologic complexity and institution-specific clinical variables, and none have been externally validated. This study aimed to develop and externally validate a machine learning model that predicts pCR after NAC in patients with breast cancer using routinely collected clinical and demographic variables. METHODS: The electronic medical records of patients with advanced breast cancer who underwent NAC before surgical resection between January 2017 and December 2020 were reviewed. Patient data from Seoul National University Bundang Hospital were divided into training and internal validation cohorts. Five machine learning techniques, including gradient boosting machine (GBM), support vector machine, random forest, decision tree, and neural network, were used to build predictive models, and the area under the receiver operating characteristic curve (AUC) was compared to select the best model. Finally, the model was validated using an independent cohort from Seoul National University Hospital. RESULTS: A total of 1,003 patients were included in the study: 287, 71, and 645 in the training, internal validation, and external validation cohorts, respectively. Overall, 36.3% of the patients achieved pCR. Among the five machine learning models, the GBM showed the highest AUC for pCR prediction (AUC, 0.903; 95% confidence interval [CI], 0.833-0.972). External validation confirmed an AUC of 0.833 (95% CI, 0.800-0.865). CONCLUSION: Commonly available clinical and demographic variables were used to develop a machine learning model for predicting pCR following NAC. External validation of the model demonstrated good discrimination power, indicating that routinely collected variables were sufficient to build a good prediction model.

A Comparison of the Prognostic Effects of Fine Needle Aspiration and Core Needle Biopsy in Patients with Breast Cancer: A Nationwide Multicenter Prospective Registry.

(1) Background: Breast core needle biopsy (CNB) is preferred over fine needle aspiration (FNA) as it has higher sensitivity and specificity and enables immunohistochemical evaluation. However, breast FNA remains widely used because of its low cost, minimally invasive nature, and quick results. Studies analyzing the effects of each test on the prognoses of patients with breast cancer are scarce and controversial, and the criteria for test selection remain unknown. (2) Methods: This study included adult female patients who underwent breast cancer surgery at 102 general hospitals. The trend of breast biopsies over time was analyzed, and the prognoses of patients with breast cancer who underwent CNB and FNA were compared. (3) Results: This study included 73,644 patients who underwent FNA (n = 8027) and CNB (n = 65,617). A multivariate Cox regression analysis showed that patients diagnosed using FNA had significantly worse overall survival (OS) and breast-cancer-specific survival (BCSS) than those diagnosed using CNB. In the subgroup analysis, patients with breast imaging reporting and data system (BI-RADS) 5 lesions, palpable tumors, or centrally located tumors had significantly worse OS and BCSS with FNA than with CNB. (4) Conclusions: CNB should be performed preferentially instead of FNA in patients with BI-RADS 5 lesions and nonpalpable or centrally located tumors.

Outcome Analysis of Combined Surgical Approaches in Advanced-stage Upper Extremity Breast Cancer-related Lymphedema.

Background: This study aimed to discuss several surgical approaches for advanced-stage breast cancer-related lymphedema and compared their treatment outcomes. Methods: The patients who underwent surgery with International Society of Lymphology stage III lymphedema were included in this study. The three surgical methods used here were (1) suction-assisted lipectomy with lymphovenous anastomosis, (2) autologous breast reconstruction with muscle-sparing transverse rectus abdominis muscle flap combined with inguinal lymph node transfer, and (3) vascularized lymph node transfer with free omental flap. Analysis of the postoperative outcomes in the patients was based on the difference in volume between patients pre- and postoperatively, LYMPH-Q questionnaire, and bioelectrical impedance analysis. Results: Eighty-seven patients with stage IIb or higher disease underwent surgery. 38 patients underwent suction-assisted lipectomy + lymphovenous anastomosis, 23 underwent autologous breast reconstruction with vascularized lymph node transfer + lymphovenous anastomosis, and 26 underwent right gastroepiploic omental vascularized lymph node transfer with lymphovenous anastomosis. The LYMPH-Q questionnaire, which evaluates patients' subjective satisfaction, showed that the autologous breast reconstruction group showed the greatest improvement, whereas in bioimpedance analysis, the omental flap group demonstrated the greatest postoperative improvement compared with preoperative values. However, suction-assisted lipectomy was considered the most effective surgical method for reducing limb volume in patients with high-stage lymphedema accompanied by fibrosis and volume increase. Conclusions: We observed slightly different clinical effects for each surgical method; however, all surgical methods demonstrated a reduction in the degree of edema and an increase in patient satisfaction.