Omission of breast surgery in selected breast cancer patients with excellent response to neoadjuvant systemic therapy

Modern neoadjuvant systemic therapy (NST) can result in high pathologic complete response rates (pCR) in triple negative (TN) and human epidermal growth factor receptor 2 positive (HER2+) breast cancer. The role of surgery is, therefore, being reconsidered in this rapidly evolving field. This report presents oncological outcomes of seven patients with TN or HER2+ breast cancer, with exceptional response to NST, and a post-NST image-guided vacuum assisted biopsy showing no residual disease (ypT0), who opted not to have breast surgery. The median age was 49 (IQR 36-61) years and the median tumour size at diagnosis was 50 (IQR 16-65) mm. All patients received breast radiotherapy and continued adjuvant systemic therapies as appropriate. At a median follow-up of 67 (IQR 61-77) months, all patients were alive and free of disease. This small case series supports the need for further research in 'exceptional responders' to provide safe, individualized patient-centred care.

Is neoadjuvant chemotherapy necessary for T2N0-1M0 hormone receptor-positive/HER2-negative breast cancer patients undergoing breast-conserving surgery?

INTRODUCTION

For HR-positive/HER2-negative patients who can undergo breast-conserving surgery (BCS) but have a tumor size of 2-5 cm or 1-3 lymph node metastases, neoadjuvant chemotherapy (NAC) is still controversial.

METHODS

Patients with T2N0-1M0 HR-positive/HER2-negative BC who underwent BCS between 2010 and 2017 were selected from the SEER database. Propensity score matching (PSM) was used to minimize the influence of confounding factors. The overall survival (OS) and breast cancer-specific survival (BCSS) of patients were estimated by Kaplan‒Meier curves and Cox proportional hazard models. Independent prognostic factors were included to construct a nomogram prediction model.

RESULTS

A total of 6475 BC patients were enrolled, of whom 553 received NAC and 5922 received adjuvant chemotherapy (AC). In the T2N0-1M0 population and T2N1M0 subgroup, AC patients before PSM had better OS and BCSS than NAC patients. After PSM, there was no significant difference in OS or BCSS between the two groups. However, in the T2N0M0 subgroup, there was no difference in survival between the AC and NAC groups before and after PSM. Stratified analysis revealed that for complete response (CR) patients, survival was roughly equivalent between the NAC and AC groups. However, the survival of no response (NR) and partial response (PR) patients was significantly worse than that of AC patients. Cox analysis revealed that radiotherapy after BCS was an independent protective factor for OS. NAC is an independent risk factor for NR and PR patients. The nomogram has good prediction efficiency.

CONCLUSION

NAC before BCS is not necessary for T2N0-1M0 HR-positive/HER2-negative BC patients.

Evaluating Magnetic Seed Localization in Targeted Axillary Dissection for Node-Positive Early Breast Cancer Patients Receiving Neoadjuvant Systemic Therapy: A Comprehensive Review and Pooled Analysis

Background/Objectives: De-escalation of axillary surgery is made possible by advancements in both neoadjuvant systemic therapy (NST) and in localisation technology for breast lesions. Magseed®, developed in 2013 by Dr. Michael Douk of Cambridge, United Kingdom, is a wire-free localisation technology that facilitates the localisation and retrieval of lymph nodes for staging. Targeted axillary dissection (TAD), which entails marked lymph node biopsy (MLNB) and sentinel lymph node biopsy (SLNB), has emerged as the preferred method to assess residual disease in post-NST node-positive patients. This systematic review and pooled analysis evaluate the performance of Magseed® in TAD. Methods: The search was carried out in PubMed and Google Scholar. An assessment of localisation, retrieval rates, concordance between MLNB and SLNB, and pathological complete response (pCR) in clinically node-positive patients post NST was undertaken. Results: Nine studies spanning 494 patients and 497 procedures were identified, with a 100% successful deployment rate, a 94.2% (468/497) [95% confidence interval (CI), 93.7-94.7] localisation rate, a 98.8% (491/497) retrieval rate, and a 68.8% (247/359) [95% CI 65.6-72.0] concordance rate. pCR was observed in 47.9% (220/459) ) [95% CI 43.3-52.6] of cases. Subgroup analysis of studies reporting the pathological status of MLNB and SLNB separately revealed an FNR of 4.2% for MLNB and 17.6% for SLNB (p = 0.0013). Mean duration of implantation was 37 days (range: 0-188). Conclusions: These findings highlight magnetic seed localisation's efficacy in TAD for NST-treated node-positive patients, aiding in accurate axillary pCR identification and safe de-escalation of axillary surgery in excellent responders.

Comparing survival outcomes between neoadjuvant and adjuvant chemotherapy within T2N1M0 stage hormone receptor-positive, HER2-negative breast cancer: a retrospective cohort study based on SEER database

BACKGROUND

Guideline recommendations for the application of neoadjuvant chemotherapy (NACT) in T2N1M0 stage hormone receptor-positive, HER2-negative (HR + /HER2-) breast cancer are ambiguous. The debate continues regarding whether NACT or adjuvant chemotherapy (ACT) offers superior survival outcomes for these patients.

MATERIALS AND METHODS

Female patients diagnosed with HR + /HER2- breast cancer at T2N1M0 stage between 2010 and 2020, were identified from the Surveillance, Epidemiology, and End Results database and divided into two groups, the NACT group and the ACT group. Propensity score matching (PSM) was utilized to establish balanced cohorts between groups, considering baseline features. Kaplan-Meier (K-M) analysis and the Cox proportional hazards model were executed to assess the efficacy of both NACT and ACT in terms of overall survival (OS) and breast cancer-specific survival (BCSS). A logistic regression model was employed to examine the association between predictive variables and response to NACT.

RESULTS

After PSM, 4,682 patients were finally included. K-M curves showed that patients receiving NACT exhibited significantly worse OS and BCSS when compared with patients undergoing ACT. Multivariable Cox analysis indicated that not achieving pathologic complete response (non-pCR) after NACT (versus ACT), was identified as an adverse prognostic factor for OS (HR 1.58, 95% CI 1.36-1.83) and BCSS (HR 1.70, 95% CI 1.44-2. 02). The logistic regression model revealed that low tumor grade independently predicted non-pCR.

CONCLUSION

Among T2N1M0 stage HR + /HER2- patients, OS and BCSS of NACT were inferior to ACT. Patients who attained non-pCR after NACT demonstrated significantly worse survival outcomes compared with those who received ACT.

[Updated surgical indications and quality and safety indicators in the management of infiltrative breast carcinoma]

OBJECTIVES

Breast surgery is the cornerstone of breast cancer treatment. Its indications and procedures are constantly evolving. To update best practices, four questions were submitted to the Senology Commission (SC) of the Collège national des gynécologues et obstétriciens français (CNGOF), covering the indications and modalities of tumor surgery: (1) initially, (2) following neoadjuvant systemic treatment, (3) in case of local recurrence, and (4) the quality and safety of care indicators applicable to this surgery.

METHODS

The CNGOF SC essentially based its responses on the clinical practice recommendations and guidelines of the French Cancer Institute concerning invasive carcinomas of the breast. Exclusion criteria were carcinoma in situ, sarcoma and axillary surgery.

RESULTS

To define the type of breast surgery, knowledge of four parameters is essential: the patient's level of risk, the presence of metastases, the size of the breast tumor and its focality (assessed by the clinical/mammography/ultrasound tripod). (1) In the case of initial management, the 6 indications for mastectomy are patient choice (particularly in case of high risk), contraindication to radiotherapy, inflammatory cancer (T4d), surgery with positive margins (after several surgical intervention), surgery that cannot be performed as a monobloc in the case of tumors with multiple foci, and poor expected aesthetic results. All other situations should be treated conservatively. (2) The same criteria apply after neoadjuvant systemic treatment, with conservative treatment still possible whatever the size (excluding carcinomatous mastitis) and focality of the initial tumor. (3) In case of local recurrence, total mastectomy is the reference treatment, with a second conservative treatment reserved for patients with no risk factors for a second recurrence, and no poor prognostic factors, after validation in a multidisciplinary meeting. (4) Four quality and safety indicators apply to breast surgery: it must be performed after obtaining a histological diagnosis, within less than 6 weeks of mammography, in a single surgery in over 80% of cases, and followed by local radiotherapy in the case of conservative treatment.

CONCLUSION

The indications and modalities of breast surgery are evolving rapidly. To improve aesthetic results, oncoplastic techniques, immediate breast reconstruction, and preservation of the skin or nipple-areolar complex need to be further developed and evaluated in the long-term. These developments must necessarily be accompanied in France by a training policy for breast surgeons.

Efficacy of Targeted Axillary Dissection With Radar Reflector Localization Before Neoadjuvant Chemotherapy

INTRODUCTION

For clinically node positive breast cancer patients treated with neoadjuvant chemotherapy (NAC), targeted axillary dissection (TAD) can be used to stage the axilla. TAD removes the sentinel lymph node (SLN) and tagged positive nodes, which can be identified via radar reflector localization (RRL). As it can be challenging to localize a previously positive node after NAC, we evaluated RRL prior to NAC.

METHODS

We performed a retrospective chart review of breast cancer patients with node positive disease treated with NAC who underwent TAD with RRL. We compared retrieval of radar reflector and clip, timing of localization, and, if a node was positive, whether the radar reflector node or SLN was positive.

RESULTS

Seventy-nine patients fulfilled inclusion criteria; 32 were placed pre-NAC (mean 187 d before surgery) and 47 were placed post-NAC (mean 7 d before surgery). For pre-NAC placement, 31 of 32 radar reflectors and 31 of 32 clips were retrieved. For post-NAC placement, 47 of 47 radar reflectors and 46 of 47 clips were retrieved. There was no significant difference in radar reflector or clip retrieval rates between pre-NAC and post-NAC groups (P = 0.41, P = 1, respectively). Thirty of 32 patients with pathologic complete response avoided an axillary lymph node dissection. Of 47 patients with a positive lymph node, 32 were both the SLN and radar reflector node, 11 were radar reflector alone, and four were the SLN.

CONCLUSIONS

RRL systems are an effective way to guide TAD, and RRL makers can be safely placed prior to NAC.

Omission of Breast Surgery in Exceptional Responders

Breast cancer management has transformed significantly over the last decades, primarily through the integration of neoadjuvant systemic therapy (NST) and the evolving understanding of tumor biology, enabling more tailored treatment strategies. The aim of this review is to critically present the historical context and contemporary evidence surrounding the potential of omission of surgery post-NST, focusing on exceptional responders who have achieved a pathologic complete response (pCR). Identifying these exceptional responders before surgery remains a challenge, however standardized image-guided biopsy may allow optimized patient selection. The safety and feasibility of omitting breast and axillary surgeries in these exceptional responders are explored in ongoing clinical trials and the reported preliminary results appear promising. Moreover, understanding patient and physician perspectives regarding the potential elimination of surgery post-NST is integral. While some patients express a preference to omit or minimize surgery, the majority of healthcare providers are intrigued by the prospect of avoiding surgical interventions and endorse further research in this field.

REPEATED BREAST-CONSERVING SURGERIES AS REFLECTION OF THE EVOLUTION IN BREAST CANCER TREATMENT (CASE REPORT WITH LITERATURE REVIEW)

The clinical case of a patient with multicentric breast cancer who underwent organ-sparing surgery after neoadjuvant chemo-radiation therapy is presented. An ipsilateral cancer recurrence was diagnosed 8 years after the first operation. The repeated organ-sparing surgery (lumpectomy) was done with a good cosmetic result and without disease progression during 1-year follow-up. The literature review shows that neoadjuvant systemic therapy accounting for molecular subtypes of cancer has radically changed breast cancer surgeries. The evolution of surgical approaches in stage I-II breast cancer patients consists in the de-escalation of surgery from mastectomy to organsparing or oncoplastic surgery, minimally directed surgery, and repeated breast-conserving surgery. De-escalation of surgical interventions in the area of the regional lymphatic collector consists in the transition from total axillary lymphatic dissection to sentinel lymph node biopsy or targeted removal of metastatic lymph nodes. The repeated breast-conserving surgery can be safely performed for ipsilateral recurrence in patients with all molecular subtypes of breast cancer.

Evaluation of quality of life in breast cancer patients who underwent breast-conserving surgery or mastectomy using real-world data

BACKGROUND

Due to advances in the fight against breast cancer, aesthetic aspects and the prevention of breast deformities are playing an important role in surgical procedures. Currently the main form of breast cancer surgery is breast-conserving surgery (BCS), and even if mastectomy (MAS) is required, oncoplastic surgery and reconstruction options can improve outcomes, including health-related quality of life (QoL) of cancer patients. The purpose of this study was to assess whether surgery options induce different outcomes in self-reported QoL in guide-line treated breast cancer patients of the Network Oncology (NO).

METHODS

This prospective Real-World-Data (RWD) study was conducted using data from the NO-clinical registry. QoL was assessed by evaluation of the European Organization of Research and Treatment Health-Related Quality of Life Core Questionnaire scale (EORTC QLQ-C30). Association factors between type of surgery options, without or with immediate breast reconstructions the EORTC QLQ-C30-scales at baseline after surgery, 6, 12, and 24 months later were analyzed with adjusted multivariate regression analysis, considering age, cancer stage, and treatment regimens, using software R.

RESULTS

A total of 623 primary breast cancer patients (all tumor stages, median age 58 (ICR: 50-68) diagnosed and guide-line treated between 2013 and 2021), 524 BCS and 99 MAS, 24 of whom received immediate breast reconstruction (MBR), were eligible for analyses. Compared with BCS patients, MBR patients self-reported considerably lower global health, physical and social functioning, and higher burden of pain and financial difficulties at baseline. In later follow-up surveys, functional scales increased and symptoms decreased in all patients, and the differences between MAS and BCS equalized. Longitudinal analyses after 24 months were obtained from 258 patients and revealed that compared to 224 BCS, the 34 MAS patients reported increased social functioning (p = 0.04).

CONCLUSIONS

At 24 months after MAS, breast cancer patients' QoL improved compared with BCS, although impairments in QoL were reported immediately after MAS. A growing expertise in surgical procedures as well as supportive care is critical to optimizing patients' well-being. These findings may be considered when counseling breast cancer patients pre- and post-surgery.

TRIAL REGISTRATION NUMBER

DRKS00013335 on 27/11/2017 retrospectively registered.

Relationship between the change in tumour-infiltrating lymphocyte level and residual tumour after neoadjuvant chemotherapy in patients with locally advanced breast cancer

To evaluate the tumour-infiltrating lymphocyte (TIL) rates in breast tissue before and after neoadjuvant chemotherapy (NAC) and their impact on survival, eighty-four patients with locally advanced breast cancer (LABC) were assessed. Pre- and post-NAC TIL levels were determined using biopsy and surgical specimens, respectively. The median TIL rate was significantly different before (17.5%) and after (5%) NAC. Pre- and postoperative Ki-67 index, molecular subtype, pre- and post-NAC TIL concentration, and preoperative residual-cancer-burden TIL were significantly associated with pathological complete response (pCR). Specifically, higher pre-NAC TIL levels were associated with higher pCR rates. Postoperative Ki-67 index and pCR, and postoperative Ki-67 index were significant predictors of disease-free (DFS) and overall survival, respectively. The independent prognostic factors for DFS were postoperative Ki-67 score (hazard ratio [HR]: 6.16; p = 0.012), post-NAC TIL score (HR: 0.42; P = 0.041), and pCR (HR: 0.10; P = 0.038). Our study confirms that higher pre-NAC and lower postoperative TIL levels may be surrogate factors for longer DFS, and postoperative TIL rate may predict post-NAC pCR in patients with LABC.

Prognosis of post-neoadjuvant therapy patients who underwent immediate breast reconstruction: a SEER-based, propensity-matched study

OBJECTIVE

The application of immediate breast reconstruction (IBR) for post-neoadjuvant therapy (NAT) patients was controversial. The aim of this study was to investigate the long-term survival outcomes of IBR for these patients.

METHODS

Data between January 2010 and November 2017 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM) was performed to reduce the influence of confounding factors between the mastectomy alone group (MA) and the mastectomy with IBR group (IBR). The rates of 5 year breast cancer-specific survival (BCSS) were compared by Kaplan-Meier curves with log-rank test.

RESULTS

The IBR was associated with improved 5-year BCSS in the IBR group before PSM (88.5 vs. 79.1%, P < 0.001). The proportion of IBR increased from 21.5% in 2010 to 28.2% in 2017. After PSM, a total of 9,610 patients were enrolled for survival analysis (4,805 in each group). In the complete response (CR) group, the 5-year BCSS rates did not differ (93.4 vs. 95.6%, P = 0.16). In the non-CR group, the 5-year BCSS rate was higher in patients who received IBR (82.5% 79.4%, P = 0.034).

CONCLUSION

In general, the application of IBR among post-NAT patients has steadily increased from 2010 to 2017. In the CR group, survival outcomes of post-NAT patients who received IBR were similar to those who received mastectomy alone. In the non-CR group, IBR was associated with potential survival benefits. More studies are expected to validate our findings.

This house believes that: MARI/TAD is better than sentinel node biopsy after PST for cN+ patients

The increasing use and effectiveness of primary systemic treatment (PST) enables tailored locoregional treatment. About one third of clinically node positive (cN+) breast cancer patients achieve pathologic complete response (pCR) of the axilla, with higher rates observed in Human Epidermal growth factor Receptor (HER)2-positive or triple negative (TN) breast cancer subtypes. Tailoring axillary treatment for patients with axillary pCR is necessary, as they are unlikely to benefit from axillary lymph node dissection (ALND), but may suffer complications and long-term morbidity such as lymphedema and impaired shoulder motion. By combining pre-PST and post-PST axillary staging techniques, ALND can be omitted in most cN + patients with pCR. Different post-PST staging techniques (MARI/TAD/SN) show low or ultra-low false negative rates for detection of residual disease. More importantly, trials using the MARI (Marking Axillary lymph nodes with Radioactive Iodine seeds) procedure or sentinel lymph node biopsy (SLNB) as axillary staging technique post-PST have already shown the safety of tailoring axillary treatment in patients with an excellent response. Tailored axillary treatment using the MARI procedure in stage I-III breast cancer resulted in 80% reduction of ALND and excellent five-year axillary recurrence free interval (aRFI) of 97%. Similar oncologic outcomes were seen for post-SLNB in stage I-II patients. The MARI technique requires only one invasive procedure pre-NST and a median of one node is removed post-PST, whereas for the SLNB and TAD techniques two to four nodes are removed. A disadvantage of the MARI technique is its use of radioactive iodine, which is subject to extensive regulations.

The Role of Sentinel Lymph Node Biopsy in Breast Cancer Patients Who Become Clinically Node-Negative Following Neo-Adjuvant Chemotherapy: A Literature Review

BACKGROUND

In clinically node-positive (cN+) breast cancer (BC) patients who become clinically node-negative (cN0) following neoadjuvant chemotherapy (NACT), sentinel lymph node biopsy (SLNB) after lymphatic mapping with lymphoscintigraphy is not widely accepted; therefore, it has become a topic of international debate.

OBJECTIVE

Our literature review aims to evaluate the current use of this surgical practice in a clinical setting and focuses on several studies published in the last six years which have contributed to the assessment of the feasibility and accuracy of this practice, highlighting its importance and oncological safety. We have considered the advantages and disadvantages of this technique compared to other suggested methods and strategies. We also evaluated the role of local irradiation therapy after SLNB and state-of-the-art SLN mapping in patients subjected to NACT.

METHODS

A comprehensive search of PubMed and Cochrane was conducted. All studies published in English from 2018 to August 2023 were evaluated.

RESULTS

Breast units are moving towards a de-escalation of axillary surgery, even in the NACT setting. The effects of these procedures on local irradiation are not very clear. Several studies have evaluated the oncological outcome of SLNB procedures. However, none of the alternative techniques proposed to lower the false negative rate (FNR) of SLNB are significant in terms of prognosis.

CONCLUSIONS

Based on these results, we can state that lymphatic mapping with SLNB in cN+ BC patients who become clinically node-negative (ycN0) following NACT is a safe procedure, with a good prognosis and low axillary failure rates.

Safety of Targeted Axillary Dissection After Neoadjuvant Therapy in Patients With Node-Positive Breast Cancer

Importance

The increasing use of neoadjuvant systemic therapy (NST) has led to substantial pathological complete response rates in patients with initially node-positive, early breast cancer, thereby questioning the need for axillary lymph node dissection (ALND). Targeted axillary dissection (TAD) is feasible for axillary staging; however, data on oncological safety are scarce.

Objective

To assess 3-year clinical outcomes in patients with node-positive breast cancer who underwent TAD alone or TAD with ALND.

Design, Setting, and Participants

The SenTa study is a prospective registry study and was conducted between January 2017 and October 2018. The registry includes 50 study centers in Germany. Patients with clinically node-positive breast cancer underwent clipping of the most suspicious lymph node (LN) before NST. After NST, the marked LNs and sentinel LNs were excised (TAD) followed by ALND according to the clinician's choice. Patients who did not undergo TAD were excluded. Data analysis was performed in April 2022 after 43 months of follow-up.

Exposure

TAD alone vs TAD with ALND.

Main Outcomes and Measures

Three-year clinical outcomes were evaluated.

Results

Of 199 female patients, the median (IQR) age was 52 (45-60) years. A total of 182 patients (91.5%) had 1 to 3 suspicious LNs; 119 received TAD alone and 80 received TAD with ALND. Unadjusted invasive disease-free survival was 82.4% (95% CI, 71.5-89.4) in the TAD with ALND group and 91.2% (95% CI, 84.2-95.1) in the TAD alone group (P = .04); axillary recurrence rates were 1.4% (95% CI, 0-54.8) and 1.8% (95% CI, 0-36.4), respectively (P = .56). Adjusted multivariate Cox regression indicated that TAD alone was not associated with an increased risk of recurrence (hazard ratio [HR], 0.83; 95% CI, 0.34-2.05; P = .69) or death (HR, 1.07; 95% CI, 0.31-3.70; P = .91). Similar results were obtained for 152 patients with clinically node-negative breast cancer after NST (invasive disease-free survival: HR, 1.26; 95% CI, 0.27-5.87; P = .77; overall survival: HR, 0.81; 95% CI, 0.15-3.83; P = .74).

Conclusions and Relevance

These results suggest that TAD alone in patients with mostly good clinical response to NST and at least 3 TAD LNs may confer survival outcomes and recurrence rates similar to TAD with ALND.

A Diagnostic Dilemma: New Enhancing Suspicious Findings on Breast MRI Following Neoadjuvant Chemotherapy

OBJECTIVE

Evaluate the incidence and outcome of new enhancing findings on breast MRI after neoadjuvant chemotherapy (NAC).

METHODS

This IRB-approved retrospective review included women with breast cancer undergoing MRI to evaluate NAC response at our institution from January 1, 1998 to March 3, 2021. Post-NAC MRIs given BI-RADS 4 or 5 with new enhancing findings were identified. Patients were excluded if they lacked pretreatment MRI or insufficient follow-up, or if the finding was a satellite of the primary tumor. Medical records and imaging studies were reviewed to identify patients and to find characteristics and outcomes.

RESULTS

Over the study period, 2880 post-NAC breast MRIs were performed. Of 128 post-NAC MRIs given BI-RADS 4 or 5 (4.4%), 35 new suspicious findings were found on 32 MRIs, incidence rate 1.1% (32/2880). Most were characterized as nonmass enhancement (17/35, 49%), followed by mass (11/35, 31%), and then focus (7/35, 20%), with an average maximum dimension of 1.3 cm (range 0.3-7.1 cm). New findings were ipsilateral to the index cancer in 20/35 (57%) of cases. Of the 35 suspicious findings, 22 underwent image-guided biopsy (62%), 1 was surgically excised (3%), 7 underwent mastectomy (20%), 5 were stable or resolved on follow-up (8%), and none were malignant. Thirty-three were benign (94%), and two were benign high-risk lesions (atypical ductal hyperplasia, radial scar) (6%).

CONCLUSION

New suspicious breast MRI findings after NAC are uncommon with a low likelihood of malignancy. Further study is warranted using multi-institutional data for this low incidence finding.

HLA-DQA1 expression is associated with prognosis and predictable with radiomics in breast cancer

BACKGROUND

High HLA-DQA1 expression is associated with a better prognosis in many cancers. However, the association between HLA-DQA1 expression and prognosis of breast cancer and the noninvasive assessment of HLA-DQA1 expression are still unclear. This study aimed to reveal the association and investigate the potential of radiomics to predict HLA-DQA1 expression in breast cancer.

METHODS

In this retrospective study, transcriptome sequencing data, medical imaging data, clinical and follow-up data were downloaded from the TCIA ( https://www.cancerimagingarchive.net/ ) and TCGA ( https://portal.gdc.cancer.gov/ ) databases. The clinical characteristic differences between the high HLA-DQA1 expression group (HHD group) and the low HLA-DQA1 expression group were explored. Gene set enrichment analysis, Kaplan‒Meier survival analysis and Cox regression were performed. Then, 107 dynamic contrast-enhanced magnetic resonance imaging features were extracted, including size, shape and texture. Using recursive feature elimination and gradient boosting machine, a radiomics model was established to predict HLA-DQA1 expression. Receiver operating characteristic (ROC) curves, precision-recall curves, calibration curves, and decision curves were used for model evaluation.

RESULTS

The HHD group had better survival outcomes. The differentially expressed genes in the HHD group were significantly enriched in oxidative phosphorylation (OXPHOS) and estrogen response early and late signalling pathways. The radiomic score (RS) output from the model was associated with HLA-DQA1 expression. The area under the ROC curves (95% CI), accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of the radiomic model were 0.866 (0.775-0.956), 0.825, 0.939, 0.7, 0.775, and 0.913 in the training set and 0.780 (0.629-0.931), 0.659, 0.81, 0.5, 0.63, and 0.714 in the validation set, respectively, showing a good prediction effect.

CONCLUSIONS

High HLA-DQA1 expression is associated with a better prognosis in breast cancer. Quantitative radiomics as a noninvasive imaging biomarker has potential value for predicting HLA-DQA1 expression.

Hyperpolarized Carbon-13 MRI in Breast Cancer

One of the hallmarks of cancer is metabolic reprogramming, including high levels of aerobic glycolysis (the Warburg effect). Pyruvate is a product of glucose metabolism, and ¹³C-MR imaging of the metabolism of hyperpolarized (HP) [1-¹³C]pyruvate (HP ¹³C-MRI) has been shown to be a potentially versatile tool for the clinical evaluation of tumor metabolism. Hyperpolarization of the ¹³C nuclear spin can increase the sensitivity of detection by 4-5 orders of magnitude. Therefore, following intravenous injection, the location of hyperpolarized ¹³C-labeled pyruvate in the body and its subsequent metabolism can be tracked using ¹³C-MRI. Hyperpolarized [¹³C]urea and [1,4-¹³C₂]fumarate are also likely to translate to the clinic in the near future as tools for imaging tissue perfusion and post-treatment tumor cell death, respectively. For clinical breast imaging, HP ¹³C-MRI can be combined with ¹H-MRI to address the need for detailed anatomical imaging combined with improved functional tumor phenotyping and very early identification of patients not responding to standard and novel neoadjuvant treatments. If the technical complexity of the hyperpolarization process and the relatively high associated costs can be reduced, then hyperpolarized ¹³C-MRI has the potential to become more widely available for large-scale clinical trials.

A prospective cohort study identifying radiologic and tumor related factors of importance for breast conserving surgery after neoadjuvant chemotherapy

INTRODUCTION

Neoadjuvant chemotherapy (NAC) is an established treatment option for early breast cancer, potentially downstaging the tumor and increasing the eligibility for breast-conserving surgery (BCS). The primary aim of this study was to assess the rate of BCS after NAC, and the secondary aim was to identify predictors of application of BCS after NAC.

MATERIALS AND METHODS

This was an observational prospective cohort study of 226 patients in the SCAN-B (Clinical Trials NCT02306096) neoadjuvant cohort during 2014-2019. Eligibility for BCS was assessed at baseline and after NAC. Uni- and multivariable logistic regression analyses were performed using covariates with clinical relevance and/or those associated with outcome (BCS versus mastectomy), including tumor subtype, by gene expression analysis.

RESULTS

The overall BCS rate was 52%, and this rate increased during the study period (from 37% to 52%). Pathological complete response was achieved in 69 patients (30%). Predictors for BCS were smaller tumor size on mammography, visibility on ultrasound, histological subtype other than lobular, benign axillary status, and a diagnosis of triple-negative or HER2-positive subtype, with a similar trend for gene expression subtypes. Mammographic density was negatively related to BCS in a dose-response pattern. In the multivariable logistic regression model, tumor stage at diagnosis and mammographic density showed the strongest association with BCS.

CONCLUSION

The rate of BCS after NAC increased during the study period to 52%. With modern treatment options for NAC the potential for tumor response and BCS eligibility might further increase.

Neoadjuvant Therapy in Nonmetastatic Breast Cancer in Kurdistan, Iraq

PURPOSE

The core management of nonmetastatic breast cancer includes surgical tumor removal by either breast-conserving surgery (BCS) or mastectomy. The use of neoadjuvant chemotherapy (NACT) has shown the potential to downstage locally advanced breast cancer (LABC) and reduce the extent of breast or axillary surgery. This study aimed to assess the treatment approach for nonmetastatic breast cancer in the Kurdistan region of Iraq and to compare its alignment with the current international recommendations for cancer treatment.

METHODS

We retrospectively reviewed the records of 1,000 patients with prespecified eligible inclusion criteria who underwent either BCS or mastectomy for nonmetastatic invasive breast cancer at oncology centers in the Kurdistan region of Iraq between the period 2016 and 2021.

RESULTS

Of 1,000 patients (median age, 47 years [range, 22-85 years]), 60.2% underwent mastectomy and 39.8% underwent BCS. The proportion of patients treated with NACT has increased over time, with 8.3% of patients receiving neoadjuvant treatment in 2016 compared with 14.2% in 2021. Similarly, BCS increased from 36.3% in 2016 to 43.7% in 2021. Most patients who underwent BCS had early breast cancer with low nodal involvement burden.

CONCLUSION

The increasing trends of BCS practice in LABC along with the increased use of NACT in the Kurdistan region in recent years comply with international guidelines. Our large multicenter, real-life series emphasizes the need to implement and discuss more conservative surgical approaches, enhanced with the broader use of NACT, through education and information programs for health providers and patients, in the context of multidisciplinary team discussions, to deliver high-quality, patient-centric breast cancer care.

Real‑world data indicated that neoadjuvant chemotherapy alone was associated with a higher risk of tumor recurrence in high‑risk breast cancer subgroup patients

Numerous clinical trials have reported equal effects of tumor control between neoadjuvant chemotherapy (NAC) and adjuvant chemotherapy (AC) in patients with breast cancer (BC). However, this conclusion has not been verified in practice. The present retrospective study evaluated if there were different risk profiles for NAC, AC and their combinative modes on disease-free survival (DFS) in patients with BC using real-world data. All women with primary unilateral Stage I-III BC and first recurrence in 2008-2018 at The Fourth Hospital of Hebei Medical University were retrospectively identified for enrollment. The four modes of chemotherapy administered for primary BC were classified as 'None', 'NAC only', 'NAC+AC' and 'AC only'. One multivariate Cox model was used to estimate the adjusted Hazard Ratio (HR) and P-value. Covariates included age, Easter Cooperative Oncology Group grade, T stage, N stage, pathology, grade, lymphovascular invasion (LVI), BC subtype, number of chemotherapy cycles and other therapies. Amongst 637 patients, who had a mean age of 48.2 years at BC diagnosis and 50.9 years at recurrence, the median DFS by the 'None' (n=27), 'NAC only' (n=47), 'NAC+AC' (n=118) and 'AC only' (n=445) modes were 31.4, 16.6, 22.6 and 28.4 months (P<0.001), respectively. Compared with the 'AC only', adjusted HR (P-value) of the 'None', 'NAC only' and 'NAC+AC' modes on tumor recurrence were 1.182 (0.551), 1.481 (0.037) and 1.102 (0.523), respectively. The adjusted HR of 'NAC only' vs. 'AC only' modes were 1.448 (P=0.157) for locoregional recurrence and 2.675 (P=0.003) for distant recurrence. Stratified analyses further indicated that the 'NAC only' mode was associated with a higher recurrence risk in T3-4, N2-3, LVI-positive, or HER2-negative subgroup patients. In conclusion, NAC alone was associated with a higher risk of tumor recurrence in high-risk BC subgroup patients in real-world data. Patient selection of chemotherapy mode was involved in practice but could not fully explain this finding. The 'inadequate' NAC was highly likely to have accounted for this observation.

Sentinel Lymph Node Biopsy in Breast Cancer Patients Undergoing Neo-Adjuvant Chemotherapy: Clinical Experience with Node-Negative and Node-Positive Disease Prior to Systemic Therapy

Background: Sentinel lymph node biopsy (SLNB) has emerged as the standard procedure to replace axillary lymph node dissection (ALND) in breast cancer (BC) patients undergoing neo-adjuvant chemotherapy (NAC). SLNB is accepted in clinically node-negative (cN0) patients; however, its role in clinically node-positive (cN+) patients is debatable. Methods: We performed a retrospective analysis of BC patients undergoing NAC and SLNB. Our aim was to evaluate the clinical significance of SLNB in the setting of NAC. This was accomplished by comparing the characteristics and oncological outcomes between cN0 and cN+ patients prior to NAC and type of axillary surgery. Results: A total of 291 patients were included in the analysis: 131 were cN0 and 160 were cN+ who became ycN0 after NAC. At a median follow-up of 43 months, axillary recurrence occurred in three cN0 (2.3%) and two cN+ (1.3%) patients. However, there were no statistically significant differences in oncological outcomes (disease-free survival, distant disease-free survival, overall survival, and breast-cancer-specific survival) between cN0 and cN+ patients nor between patients treated with SLNB only or ALND. Conclusions: SLNB in the setting of NAC is an acceptable procedure with a general good prognosis and low axillary failure rates for both cN0 and cN+ patients.

Comparing survival outcomes between neoadjuvant and adjuvant chemotherapy within breast cancer subtypes and stages among older women: a SEER-Medicare analysis

BACKGROUND

This study aimed to compare survival outcomes of neoadjuvant (NAC) and adjuvant chemotherapy (AdC) within each breast cancer subtype and stage among older women.

METHODS

Older (≥ 66 years) women newly diagnosed with stage I-III invasive ductal breast cancer during 2010-2017 and treated with both chemotherapy and surgery within one year were identified from the Surveillance, Epidemiology, and End Results (SEER)-Medicare database. Analyses were performed within each of six groups, jointly defined based on subtype (hormone receptor [HR]-positive/human epidermal growth factor receptor 2 [HER2]-negative, HER2 + , and triple-negative) and stage (I-II and III). Kaplan-Meier curves and multivariable Cox models were used to compare overall and recurrence-free survival between NAC and AdC, with optimal full matching performed for confounding adjustment.

RESULTS

Among 8,495 included patients, 8,329 (20.6% received NAC) remained after matching. Before multiple testing adjustment, Cox models showed that NAC was associated with a lower hazard for death among stage III HER2 + patients (hazard ratio = 0.347, 95% confidence interval CI 0.161-0.745) but a higher hazard for death among triple-negative patients (stage I-II: hazard ratio = 1.558, 95% CI 1.024-2.370; stage III: hazard ratio = 2.453; 95% CI 1.254-4.797). A higher hazard for death/recurrence was associated with NAC among stage I-II HR + /HER2- patients (hazard ratio = 1.305, 95% CI 1.007-1.693). No significant difference remained after multiple testing adjustment.

CONCLUSIONS

The opposite trends (before multiple testing adjustment) of survival comparisons for advanced HER2 + and triple-negative disease warrant further research. Caution is needed due to study limitations such as cancer stage validity.

Estimating the Benefit of Preoperative Systemic Therapy to Reduce the Extent of Breast Cancer Surgery: Current Standard and Future Directions

Once reserved for locally advanced tumors which were deemed inoperable at presentation, preoperative systemic therapy (PST) is nowadays increasingly used to treat early breast cancer. PST allows for in vivo assessment of tumor response, for tailoring of adjuvant systemic therapy and for de-escalation of breast and the axillary surgery. Increased rates of pathological complete response together with more accurate response assessment and surgical planning have led to a significant reduction in surgical morbidity. While surgical assessment remains the standard of care, ongoing studies are evaluating whether surgery can be omitted in patients who achieve a complete pathological response. In this chapter, I will review the impact of PST on surgical de-escalation and the data supporting the safety of this approach.

Assessment and Response to Neoadjuvant Treatments in Breast Cancer: Current Practice, Response Monitoring, Future Approaches and Perspectives

Neoadjuvant treatments (NAT) for breast cancer (BC) consist in the administration of chemotherapy-more rarely endocrine therapy-before surgery. Firstly, it was introduced 50 years ago to downsize locally advanced (inoperable) BCs. NAT are now widespread and so effective to be used also at the early stage of the disease. NAT are heterogeneous in terms of therapeutic patterns, class of used drugs, dosage, and duration. The poly-chemotherapy regimen and administration schedule are established by a multi-disciplinary team, according to the stage of disease, the tumor subtype and the age, the physical status, and the drug sensitivity of BC patients. Consequently, an accurate monitoring of treatment response can provide significant clinical advantages, such as the treatment de-escalation in case of early recognition of complete response or, on the contrary, the switch to an alternative treatment path in case of early detection of resistance to the ongoing therapy. Future is going toward increasingly personalized therapies and the prediction of individual response to treatment is the key to practice customized care pathways, preserving oncological safety and effectiveness. To gain such goal, the development of an accurate monitoring system, reproducible and reliable alone or as part of more complex diagnostic algorithms, will be promising.

"This house believes that: Sentinel node biopsy alone is better than TAD after NACT for cN+ patients"

The increased use of neoadjuvant chemotherapy (NACT) has changed the approach to breast surgery. NACT allows de-escalation of surgery by both increasing breast conservation rates (up to 40%), the initial goal of this chemotherapy, and in particular it permits reduces axillary surgery. Furthermore, in relation to the molecular characteristics of the tumor we can have a pathological complete response (pCR) ranging from 20 to 80%. In clinically node positive (cN+) patients who converted to clinically node-negative (cN0) various prospective studies have demonstrated that the false negative rate (FNR) of the sentinel node biopsy (SNB) were higher than the acceptable 10% and strategies to reduce the FNR in cN + patients are being investigated. But all the effort to reduce the FNR does not have clinical prognostic significance. This has already been demonstrated in the literature in different randomized trials with long term follow up. The 10-year follow-up of our study confirmed our preliminary data that the use of standard SNB without the use of clip is acceptable in cN1/2 patients who become cN0 after NAT and will not translate into a worse outcome. In fact, the axillary recurrences were less than 2%. Similar positive data with different follow up were also confirmed by other studies that used SNB alone without TAD. All these studies, with encouraging results on the follow up, confirm that SN surgery alone for selected patients who have an excellent response to NACT is rationale and not oncologically inferior to AD during a short- and long-term follow-up.

Residual Disease Burden After Neoadjuvant Therapy Among US Patients With High-Risk HER2-positive Early-Stage Breast Cancer: A Population Effectiveness Model

BACKGROUND

Approximately half of patients with high-risk HER2-positive early-stage breast cancer (ESBC) do not have pathologic complete response (pCR) after neoadjuvant therapy. The residual burden of disease among this population has not been previously quantified.

MATERIALS AND METHODS

We used decision-modeling techniques to simulate recurrence, progression from locoregional to distant cancer, breast cancer-related mortality, and mortality from other causes over a 10-year period in a hypothetical cohort. We derived progression probabilities primarily from the KATHERINE trial of T-DM1 (ado-trastuzumab emtansine) and mortality outcomes from the published literature. Modeled outcomes included recurrences, breast cancer deaths, deaths from other causes, direct medical costs, and costs due to lost productivity. To estimate the residual disease burden, we compared outcomes from a cohort of patients treated with T-DM1 versus a hypothetical cohort with no disease recurrence.

RESULTS

We estimated that 9,300 people would experience incident high-risk HER2-positive ESBC in the United States in 2021 based on cancer surveillance databases, clinical trial data, and expert opinion. We estimated that, in this group, 2,118 would experience disease recurrence, including 1,576 distant recurrences, and 1,358 would experience breast cancer deaths. This residual disease burden resulted in 6,435 life-years lost versus the recurrence-free cohort, and healthcare-related costs totaling $644 million, primarily associated with treating distant cancers.

CONCLUSION

Patients with HER2-positive ESBC who do not achieve pCR after neoadjuvant therapy are at ongoing risk of recurrence despite the effectiveness of neoadjuvant treatment. There is substantial clinical and economic value in further reducing the residual disease burden in this population.

Breast Cancer Statistics, 2022

This article is the American Cancer Society's update on female breast cancer statistics in the United States, including population-based data on incidence, mortality, survival, and mammography screening. Breast cancer incidence rates have risen in most of the past four decades; during the most recent data years (2010-2019), the rate increased by 0.5% annually, largely driven by localized-stage and hormone receptor-positive disease. In contrast, breast cancer mortality rates have declined steadily since their peak in 1989, albeit at a slower pace in recent years (1.3% annually from 2011 to 2020) than in the previous decade (1.9% annually from 2002 to 2011). In total, the death rate dropped by 43% during 1989-2020, translating to 460,000 fewer breast cancer deaths during that time. The death rate declined similarly for women of all racial/ethnic groups except American Indians/Alaska Natives, among whom the rates were stable. However, despite a lower incidence rate in Black versus White women (127.8 vs. 133.7 per 100,000), the racial disparity in breast cancer mortality remained unwavering, with the death rate 40% higher in Black women overall (27.6 vs. 19.7 deaths per 100,000 in 2016-2020) and two-fold higher among adult women younger than 50 years (12.1 vs. 6.5 deaths per 100,000). Black women have the lowest 5-year relative survival of any racial/ethnic group for every molecular subtype and stage of disease (except stage I), with the largest Black-White gaps in absolute terms for hormone receptor-positive/human epidermal growth factor receptor 2-negative disease (88% vs. 96%), hormone receptor-negative/human epidermal growth factor receptor 2-positive disease (78% vs. 86%), and stage III disease (64% vs. 77%). Progress against breast cancer mortality could be accelerated by mitigating racial disparities through increased access to high-quality screening and treatment via nationwide Medicaid expansion and partnerships between community stakeholders, advocacy organizations, and health systems.

Surgical options of the breast and clinical outcomes of breast cancer patients after neoadjuvant chemotherapy: A single-center retrospective study

Background

Neoadjuvant chemotherapy (NAC) has evolved significantly and has been widely accepted for downstaging disease in early-stage and locally advanced breast cancer patients. Since the optimal surgical intervention for patients receiving NAC remains controversial, we aim to investigate the survival outcome of patients treated with different surgical management.

Methods

A retrospective, nested case-control study was conducted in patients with invasive breast cancer that underwent NAC at Fudan University Shanghai Cancer Center from January 2010 to June 2019. Based on surgical intervention, patients were divided into mastectomy and breast conservation groups. Patients were matched on age at diagnosis, menopausal status, the year of the surgery, post neoadjuvant therapy pathological tumor (ypT) stage, post neoadjuvant therapy pathological node (ypN) stage, molecular subtypes, and axillary surgery by propensity score matching.

Results

A total of 2080 patients were enrolled in this study. Among them, 1819 (87.5%) patients were categorized as mastectomy group, and 261 (12.5%) patients were classed as breast conservation group. Over 9-years of research, the proportion of breast conservation steadily increased in patients after NAC. Data showed that younger (P&lt;0.001) and pre-menopausal (P&lt;0.001) patients with normal BMI (P=0.022) were more likely to receive breast conservation. Patients at advanced ypT stage (P&lt;0.001), ypN stage (P&lt;0.001), and clinical TNM stage (P&lt;0.001) were more often to undergo mastectomy, while breast conservation rate was significantly higher in patients with triple-negative tumors (P=0.023). Compared with the mastectomy group, significant benefits in overall survival were observed in patients who received breast conservation (Hazard ratio 0.41, [95% confidence interval: 0.18-0.97]; p=0.049) in the matched cohort. There was no statistical difference between groups related to disease-free survival and locoregional recurrence.

Conclusions

Tumor biology can significantly impact the surgical decision in patients administrated with NAC. Breast conservation was a safe alternative for mastectomy in the NAC setting without compromising survival outcomes and locoregional control.

Pharmacometabolomics reveals urinary diacetylspermine as a biomarker of doxorubicin effectiveness in triple negative breast cancer

Triple-negative breast cancer (TNBC) patients receive chemotherapy treatment, including doxorubicin, due to the lack of targeted therapies. Drug resistance is a major cause of treatment failure in TNBC and therefore, there is a need to identify biomarkers that determine effective drug response. A pharmacometabolomics study was performed using doxorubicin sensitive and resistant TNBC patient-derived xenograft (PDX) models to detect urinary metabolic biomarkers of treatment effectiveness. Evaluation of metabolite production was assessed by directly studying tumor levels in TNBC-PDX mice and human subjects. Metabolic flux leading to biomarker production was determined using stable isotope-labeled tracers in TNBC-PDX ex vivo tissue slices. Findings were validated in 12-h urine samples from control (n = 200), ER+/PR+ (n = 200), ER+/PR+/HER2+ (n = 36), HER2+ (n = 81) and TNBC (n = 200) subjects. Diacetylspermine was identified as a urine metabolite that robustly changed in response to effective doxorubicin treatment, which persisted after the final dose. Urine diacetylspermine was produced by the tumor and correlated with tumor volume. Ex vivo tumor slices revealed that doxorubicin directly increases diacetylspermine production by increasing tumor spermidine/spermine N¹-acetyltransferase 1 expression and activity, which was corroborated by elevated polyamine flux. In breast cancer patients, tumor diacetylspermine was elevated compared to matched non-cancerous tissue and increased in HER2+ and TNBC compared to ER+ subtypes. Urine diacetylspermine was associated with breast cancer tumor volume and poor tumor grade. This study describes a pharmacometabolomics strategy for identifying cancer metabolic biomarkers that indicate drug response. Our findings characterize urine diacetylspermine as a non-invasive biomarker of doxorubicin effectiveness in TNBC.

Prognostic nomogram for female patients suffering from non-metastatic Her2 positive breast cancer: A SEER-based study

This paper aimed at constructing and validating a novel prognostic nomogram, so that physicians forecast the overall survival (OS) rates of female patients suffering from non-metastatic human epidermal growth element receptor-2 (HER2) positive breast. Information of primary female her2 positive breast cancer patients without metastasis was obtained from the Surveillance, Epidemiology, and End Results (SEER) database with given inclusion and exclusion standards. Independent variables were obtained greatly by performing univariable and multivariate analyses. Based on those independent predictors, a novel prognostic nomogram was constructed for predicting the survival of those with 3- and 5-year OS. Then, concordance index (C-index), receiver operating characteristic curve (ROC), and calibration plot were adopted for the assessment of the predictive power of the nomogram. A total of 36,083 eligible patients were classified into a training cohort (n = 25,259) and a verification cohort (n = 10,824) randomly. According to the identification of multivariate analysis, survival was predicted by age at diagnosis, marital status, race, site, T stage, N stage, progesterone receptor (PR) status, estrogen receptor (ER) status, surgery, radiation, and chemotherapy independently. A nomogram was established by applying the training cohort. The nomogram displayed excellent discrimination and performance as indicated by the C-index (0.764, 95% confidence interval: 0.756-0.772), and the 3- and 5-year area under the curve of ROC (AUC) values (0.760 and 0.692 respectively). The calibration plots for forecasting the 3- and 5-year OS were in great agreement. The OS for female her2 positive breast cancer patients without metastasis was predicted by constructing a nomogram on basis of the SEER database. A precise survival prediction could be offered for each patient.

MRI to assess response after neoadjuvant chemotherapy in breast cancer subtypes: a systematic review and meta-analysis

This meta-analysis aimed to estimate and compare sensitivity, specificity, positive- (PPV) and negative predictive value (NPV) of magnetic resonance imaging (MRI) for predicting pathological complete remission (pCR) after neoadjuvant chemotherapy (NAC) in patients with early-stage breast cancer. We stratified for molecular subtype by immunohistochemistry (IHC) and explored the impact of other factors. Two researchers systematically searched PUBMED and EMBASE to select relevant studies and extract data. For meta-analysis of sensitivity and specificity, we used bivariate random-effects models. Twenty-six included studies contained 4497 patients. There was a significant impact of IHC subtype on post-NAC MRI accuracy (p = 0.0082) for pCR. The pooled sensitivity was 0.67 [95% CI 0.58-0.74] for the HR-/HER2-, 0.65 [95% CI 0.56-0.73] for the HR-/HER2+, 0.55 [95% CI 0.45-0.64] for the HR+/HER2- and 0.60 [95% CI 0.50-0.70] for the HR+/HER2+ subtype. The pooled specificity was 0.85 [95% CI 0.81-0.88] for the HR-/HER2-, 0.81 [95% CI 0.74-0.86] for the HR-/HER2+, 0.88[95% CI 0.84-0.91] for the HR+/HER2- and 0.74 [95% CI 0.63-0.83] for the HR+/HER2+ subtype. The PPV was highest in the HR-/HER2- subtype and lowest in the HR+/HER2- subtype. MRI field strength of 3.0 T was associated with a higher sensitivity compared to 1.5 T (p = 0.00063). The accuracy of MRI for predicting pCR depends on molecular subtype, which should be taken into account in clinical practice. Higher MRI field strength positively impacts accuracy. When intervention trials based on MRI response evaluation are designed, the impact of IHC subtype and field strength on MR accuracy should be considered.

Neoadjuvant Chemotherapy and Nodal Response Rates in Luminal Breast Cancer: Effects of Age and Tumor Ki67

BACKGROUND

Neoadjuvant chemotherapy (NAC) is standard for most triple-negative and human epidermal growth factor receptor 2 (HER2)+ breast cancers, and frequently downstages node-positive (cN+) disease, permitting omission of axillary dissection. In estrogen receptor (ER)+/HER2- disease, response rates are lower. Whether Ki67 is associated with axillary downstaging in ER+/HER2- disease is unknown.

METHODS

With institutional review board approval, we queried our institutional database to identify all patients with primary ER+/HER2- biopsy-proven cN+ breast cancer treated with NAC followed by surgery from January 2012 to December 2021. Nodal pathologic complete response (pCR) rates were evaluated by pretreatment Ki67 and patient age.

RESULTS

315 patients (median age 50 years) were included. Nodal pCR rate was 24.8% (78/315) and was higher in patients aged < 50 years than ≥ 50 years (31.8% versus 17.7%, p = 0.004). Ki67 was available on 236 patients (74.9%). Median Ki67 was 29.0% (range 1-98%) and did not differ by age category (p = 0.23). Patients with nodal pCR had higher Ki67 (median 40.3% versus 25.0%, p < 0.001). Nodal pCR rates were 28.4% (Ki67 ≥ 20%) versus 8.1% (Ki67 < 20%) (p < 0.001). On multivariable analysis, Ki67 and age category were predictive of nodal pCR. Combining these two parameters together, nodal pCR rates in age < 50 years were 35.8% when Ki67 ≥ 20% versus 14.3% with Ki67 < 20% (p = 0.02). In contrast, for age ≥ 50 years, nodal pCR was 21.0% for Ki67 ≥ 20% versus 2.6% with Ki67 < 20% (p = 0.008).

CONCLUSIONS

In ER+/HER2- breast cancer, nodal downstaging with NAC is associated with age (< 50 years) and Ki67 (≥ 20%). Age and Ki67 should be considered for NAC decision-making and can identify patients with high rates of nodal downstaging (36%) who would benefit from NAC to enable axillary preservation.

Nodal Pathologic Complete Response Rates in Luminal Breast Cancer Vary by Genomic Risk

BACKGROUND

Although an advantage of neoadjuvant chemotherapy (NAC) is eradication of axillary disease, nodal pCR rates are much lower for ER+/HER2- breast cancer than other subtypes. We sought to evaluate the association of genomic risk with nodal pCR in ER+/HER2- disease.

METHODS

Patients with ER+/HER2- clinically-node-positive (cT0-cT4d/cN1-cN3/cM0) breast cancer treated with NAC and surgery 2010-2018 in the National Cancer Database were identified. Low genomic risk was classified as Oncotype Dx Recurrence Score (RS) 0-25, or Mammaprint 70-gene or RS coded as "Low." High genomic risk included RS >25, or 70-gene or RS coded as "High." Nodal pCR was compared between patients with high versus low genomic risk by using chi-square tests and multivariable logistic regression.

RESULTS

Of 15,698 patients, genomic risk was available for 692 of 15,698 (4.4%). High genomic risk was similar between patients aged <50 years versus 50+ (50.8% vs. 57.3%, p = 0.10). Nodal pCR was higher in high genomic risk (25.0%) than low genomic risk (10.4%, p < 0.001). This difference was observed both for patients aged <50 years (29.9% vs. 9.8%) and aged ≥50 years (22.7% vs. 10.8%). On multivariable analysis adjusted for potential confounding variables, including age, grade, and PR status, genomic risk was independently associated with decreased odds of residual nodal disease (odds ratio 0.49, p = 0.002).

CONCLUSIONS

For patients with node-positive ER+/HER2- breast cancer treated with NAC, nodal pCR was highest in patients aged <50 years with high genomic risk tumors. In contrast, nodal pCR rates were low in patients with low genomic risk tumors, regardless of age. This information may help when counseling patients regarding axillary management.

Prediction of the Pathological Response to Neoadjuvant Chemotherapy in Breast Cancer Patients With MRI-Radiomics: A Systematic Review and Meta-analysis

We performed a systematic review and a meta-analysis of studies using MRI-radiomics for predicting the pathological complete response in breast cancer patients undergoing neoadjuvant therapy , and we evaluated their methodological quality using the radiomics-quality-score (RQS). Random effects meta-analysis was performed pooling area under the receiver operating characteristics curves. Publication-bias was assessed using the Egger's test and visually inspecting the funnel plot. Forty-three studies were included in the qualitative review and 34 in the meta-analysis. Summary area under the receiver operating characteristics curve was 0,78 (95%CI:0,74-0,81). Heterogeneity according to the I² statistic was substantial (71%) and there was no evidence of publication bias (P-value = 0,2). The average RQS was 12,7 (range:-1-26), with an intra-class correlation coefficient of 0.93 (95%CI:0.61-0.97). Year of publication, field intensity and synthetic RQS score do not appear to be moderators of the effect (P-value = 0.36, P-value = 0.28 and P-value = 0.92, respectively). MRI-radiomics may predict response to neoadjuvant therapy in breast cancer patients but the heterogeneity of the current studies is still substantial.

Factors Influencing Non-sentinel Lymph Node Involvement in Patients with Positive Sentinel Lymph Node(s) After Neoadjuvant Chemotherapy for Breast Cancer

BACKGROUND

When a positive sentinel lymph node (SLN) is identified after neoadjuvant chemotherapy (NAC), completion axillary lymph node dissection (cALND) is generally recommended. We sought to evaluate the rate of non-SLN positivity and factors influencing this in patients with a positive SLN following NAC.

METHODS

We identified all patients at our hospital between 2006 and 2021 with a positive SLN (> 0.2 mm) following NAC who underwent cALND. Rates of positive non-SLN (NSLN) on cALND were compared by nodal status. Chi-square tests and multivariable logistic regression were used to assess factors predictive of positive NSLN and overall nodal burden.

RESULTS

Overall, 229 cases (177 cN+, 52 cN0 prior to NAC) with positive SLN(s) after NAC underwent cALND. Additional NSLN involvement was found in 129/229 (56.3%) patients, including 24/52 (46.2%) cN0 and 105/177 (59.3%) cN+ patients (p = 0.09). There was a trend for patients with SLN micrometastases to be less likely to have positive NSLN(s) than those with SLN macrometastases (38.5% vs. 58.6%; p = 0.05). Subgroup analyses showed no clinicopathologic factors significantly associated with additional axillary involvement for initially cN0 patients. Factors found to significantly influence NSLN positivity in the initially cN+ subgroup were HER2 status, multicentricity/multifocality, number of positive SLNs, and size of SLN metastasis. SLN metastasis size > 5 mm and three or more positive SLNs exerted the greatest influence on NSLN positivity.

CONCLUSION

Rates of nodal positivity on cALND in the setting of positive SLN after NAC are high, supporting the current standard of routine cALND. In cN+ disease, NSLN positivity varies by tumor biology, multicentricity/multifocality, number of positive SLNs, and SLN metastasis size.

Breast Cancer Patients: Who Would Benefit from Neoadjuvant Chemotherapies?

Neoadjuvant chemotherapy (NACT) was developed with the aims of shrinking tumors or stopping cancer cells from spreading before surgery. Unfortunately, not all breast cancer patients will benefit from NACT, and thus, patients must weigh the risks and benefits of treatment prior to the initiation of therapy. Currently, the data for predicting the efficacy of NACT is limited. Molecular testing, such as Oncotype DX, MammaPrint, and Curebest 95GC, have been developed to assist which breast cancer patients will benefit from the treatment. Patients with an increased level of Human Leukocyte Antigen-DR isotype, tumor-infiltrating lymphocytes, Fizzy-related protein homolog, and a decreased level of tumor-associated macrophages appear to benefit most from NACT.

Update on sentinel node pathology in breast cancer

Pathologic examination of the sentinel lymph nodes (SLNs) in patients with breast cancer has been impacted by the publication of practicing changing trials over the last decade. With evidence from the ACOSOG Z0011 trial to suggest that there is no significant benefit to axillary lymph node dissection (ALND) in early-stage breast cancer patients with up to 2 positive SLNs, the rate of ALND, and in turn, intraoperative evaluation of SLNs has significantly decreased. It is of limited clinical significance to pursue multiple levels and cytokeratin immunohistochemistry to detect occult small metastases, such as isolated tumor cells and micrometastases, in this setting. Patients treated with neoadjuvant therapy, who represent a population with more extensive disease and aggressive tumor biology, were not included in Z0011 and similar trials, and thus, the evidence cannot be extrapolated to them. Recent trials have supported the safety and accuracy of sentinel lymph node biopsy (SLNB) in these patients when clinically node negative at the time of surgery. ALND remains the standard of care for any amount of residual disease in the SLNs and intraoperative evaluation of SLNs is still of value for real time surgical decision making. Given the potential prognostic significance of residual small metastases in treated lymph nodes, as well as the decreased false negative rate with the use of cytokeratin immunohistochemistry (IHC), it may be reasonable to maintain a low threshold for the use of cytokeratin IHC in post-neoadjuvant cases. Further recommendations for patients treated with neoadjuvant therapy await outcomes data from ongoing clinical trials. This review will provide an evidence-based discussion of best practices in SLN evaluation.

Chemotherapy-Induced Collagen IV Drives Cancer Cell Motility through Activation of Src and Focal Adhesion Kinase

Triple-negative breast cancer (TNBC) is the most aggressive and deadly subtype of breast cancer, accounting for 30,000 cases annually in the United States. While there are several clinical trials ongoing to identify new agents to treat TNBC, the majority of patients with TNBC are treated with anthracycline- or taxane-based chemotherapies in the neoadjuvant setting, followed by surgical resection and adjuvant chemotherapy. While many patients respond well to this approach, as many as 25% will suffer local or metastatic recurrence within 5 years. Understanding the mechanisms that drive recurrence after chemotherapy treatment is critical to improving survival for patients with TNBC. It is well established that the extracellular matrix (ECM), which provides structure and support to tissues, is a major driver of tumor growth, local invasion, and dissemination of cancer cells to distant metastatic sites. In the present study, we show that decellularized ECM (dECM) obtained from chemotherapy-treated mice increases motility of treatment-naïve breast cancer cells compared with vehicle-treated dECM. Tandem-mass-tag proteomics revealed that anthracycline- and taxane-based chemotherapies induce drug-specific changes in tumor ECM composition. The basement membrane protein collagen IV was significantly upregulated in the ECM of chemotherapy-treated mice and patients treated with neoadjuvant chemotherapy. Collagen IV drove invasion via activation of Src and focal adhesion kinase signaling downstream of integrin α1 and α2, and inhibition of collagen IV-driven signaling decreased motility in chemotherapy-treated dECM. These studies provide a novel mechanism by which chemotherapy may induce metastasis via its effects on ECM composition.

SIGNIFICANCE

Cytotoxic chemotherapy induces significant changes in the composition of tumor ECM, inducing a more invasive and aggressive phenotype in residual tumor cells following chemotherapy.

A 10-miRNA risk score-based prediction model for pathological complete response to neoadjuvant chemotherapy in hormone receptor-positive breast cancer

Patients with hormone receptor (HR)-positive tumors breast cancer usually experience a relatively low pathological complete response (pCR) to neoadjuvant chemotherapy (NAC). Here, we derived a 10-microRNA risk score (10-miRNA RS)-based model with better performance in the prediction of pCR and validated its relation with the disease-free survival (DFS) in 755 HR-positive breast cancer patients (273, 265, and 217 in the training, internal, and external validation sets, respectively). This model, presented as a nomogram, included four parameters: the 10-miRNA RS found in our previous study, progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) status, and volume transfer constant (K^trans). Favorable calibration and discrimination of 10-miRNA RS-based model with areas under the curve (AUC) of 0.865, 0.811, and 0.804 were shown in the training, internal, and external validation sets, respectively. Patients who have higher nomogram score (>92.2) with NAC treatment would have longer DFS (hazard ratio=0.57; 95%CI: 0.39-0.83; P=0.004). In summary, our data showed the 10-miRNA RS-based model could precisely identify more patients who can attain pCR to NAC, which may help clinicians formulate the personalized initial treatment strategy and consequently achieves better clinical prognosis for patients with HR-positive breast cancer.

Meta-Analysis of Shrinkage Mode After Neoadjuvant Chemotherapy for Breast Cancers: Association With Hormonal Receptor

Background

Patients with concentric shrinkage mode after neoadjuvant chemotherapy (NAC) is considered to be ideal candidates for breast conserving treatment (BCT). While, what proportion of patients would represent CSM have not been well defined. This study was conducted to pool the rates of concentric shrinkage mode (CSM) in patients undergoing NAC, determine the impact of hormonal receptor on the shrinkage mode after NAC and estimate the rates of the CSM in various subgroups.

Methods

We conducted a systematic review following the guidelines for Meta-Analyses and Systematic reviews for the PRISMA guidelines. We systematically searched the literature about shrinkage mode after NAC from PubMed, Web of Science, Embase, The Cochrane Library, CNKI, Wanfang database published from January 2002 to June 2020 on breast cancer shrinkage mode after NAC and carefully screened the literature by using eligibility criteria: (1) patients with primary breast cancer treated with NAC; (2) publications with available data of shrinkage mode measured by magnetic resonance imaging (MRI), or data of pathology and hormonal receptor. The association between shrinkage mode and hormonal receptor was estimated using Stata 15.1 software.

Results

This analysis included a total of 2434 tumors from 23 papers. The included studies were heterogeneous (I2 = 89.4%, P<0.01). Random effects model was used to estimate the overall rates of CSM: 56.6% [95%CI (50.5%, 62.7%)]. According to the analysis of hormonal receptor, 10 of the paper was included for HR+ (hormone receptor positive) type analysis and the rate of CSM for HR+ type was 45.7% [95%CI (36.4%, 55.0%)]; 9 of the paper was used for HR- type (hormone receptor negative) analysis and the incidence of HR-CSM is 63.1% [95%CI (50.0%, 76.1%)]; with HR+ type as the control, the OR of the HR- CSM rate is 2.32 (1.32, 4.08) folds of HR+ type. From subgroup analyses, the CSM% of luminal A, luminal B, Her2+, and triple negative were 29.7% (16.5%, 42.8%); 47.2% (19.1%, 75.3%); 59.0% (39.7%, 78.3%); 66.2% (52.8%, 79.6%), respectively.

Conclusions

Breast cancer patients undergoing NAC did not get an ideal odds ratio of CSM. The incidence of CSM in breast cancer after NAC is associated with hormonal receptor. Patients with triple-negative breast cancers have the highest rates of CSM after NAC. More care should be taken to select patients with the luminal subtypes for BCT throughout NAC.

Neoadjuvant chemotherapy use trends among older women with breast cancer: 2010-2017

PURPOSE

This study assessed chemotherapy use trends before (neoadjuvant chemotherapy [NAC]) or after surgery (adjuvant chemotherapy [AdC]) among older women with breast cancer and examined factors related to NAC receipt.

METHODS

Women (> 65 years) diagnosed with stage I-III breast cancer during 2010-2017 who received NAC or AdC were identified from the Surveillance, Epidemiology, and End Results (SEER)-Medicare database. All patients were stratified into six strata based on subtype (hormone receptor-positive/human epidermal growth factor receptor 2-negative [HR + /HER2-], HER2 + , and triple-negative breast cancer [TNBC]) and stage (I-II and III). Cochran-Armitage tests were performed to test temporal trends of NAC use in each stratum. Multivariable logistic regression analyses were performed to identify factors (sociodemographic and clinical) related to NAC use.

RESULTS

Among included older (mean ± standard deviation: 72.3 ± 5.2 years) women (N = 8,495) with stage I-III breast cancer, NAC use increased from 11.7% (2010) to 32.6% (2017). Significant increases in NAC were found in all strata (p < .0001) with more substantial increases in HER2 + disease and TNBC compared to HR + /HER2- disease. Multivariable logistic regressions identified the youngest age category (66-69 years) and later stage as significant (p < 0.05) predictors of NAC receipt in most strata, in addition to diagnosis year.

CONCLUSION

Similar to the overall breast cancer population, NAC use increased among a population of older women. NAC was received by most patients with stage III HER2 + disease or TNBC in more recent years and was more common among younger elderly women and those in stage III.

Prospective Evaluation of Radar-Localized Reflector-Directed Targeted Axillary Dissection in Node-Positive Breast Cancer Patients after Neoadjuvant Systemic Therapy

BACKGROUND

This is a prospective, single-institution study to evaluate feasibility and accuracy of radar-localized reflector (RLR)-targeted axillary dissection (TAD) in node-positive breast cancer patients after neoadjuvant systemic therapy (NST).

METHODS

Patients with biopsy-proven T1-2, N1-3 disease were eligible. Before NST, a marker clip and/or RLR was placed into the positive node. After NST, RLR was inserted if not placed previously. All patients underwent RLR TAD followed by axillary lymph node dissection (ALND). Primary end points of the trial were feasibility of RLR TAD and false negative rate (FNR).

RESULTS

Between 2017 and 2021, 101 patients with N1-3 disease underwent NST. Five patients withdrew from the study, 1 was ineligible, and there were 9 technical failures, thus our final study cohort comprised 86 patients. RLR TAD was performed with probe guidance and confirmed with intraoperative specimen radiograph. After RLR TAD, ALND was performed. Median number of RLR TAD nodes removed was 2 (range 1-10), and the RLR TAD nodes remained positive in 56 patients. Median number of ALND nodes removed was 18 (range 4-46). Accounting for 9 technical failures, feasibility was 90%. All technical failures occurred with attempted placement of RLR after NST. Feasibility rate was 100% when RLR placement occurred at diagnosis. Of the evaluable 86 patients, RLR TAD accurately predicted axillary status in 83 patients, with FNR of 5.1%.

CONCLUSION

We demonstrate high accuracy of RLR TAD, especially when RLR is placed before NST. For patients who present with N1-3 disease, this is another step towards axillary surgery de-escalation strategies.

Diagnosing Pathologic Complete Response in the Breast After Neoadjuvant Systemic Treatment of Breast Cancer Patients by Minimal Invasive Biopsy: Oral Presentation at the San Antonio Breast Cancer Symposium on Friday, December 13, 2019, Program Number GS5-03

OBJECTIVE

We evaluated the ability of minimally invasive, image-guided vacuum-assisted biopsy (VAB) to reliably diagnose a pathologic complete response in the breast (pCR-B).

SUMMARY BACKGROUND DATA

Neoadjuvant systemic treatment (NST) elicits a pathologic complete response in up to 80% of women with breast cancer. In such cases, breast surgery, the gold standard for confirming pCR-B, may be considered overtreatment.

METHODS

This multicenter, prospective trial enrolled 452 women presenting with initial stage 1-3 breast cancer of all biological subtypes. Fifty-four women dropped out; 398 were included in the full analysis. All participants had an imaging-confirmed partial or complete response to NST and underwent study-specific image-guided VAB before guideline-adherent breast surgery. The primary endpoint was the false-negative rate (FNR) of VAB-confirmed pCR-B.

RESULTS

Image-guided VAB alone did not detect surgically confirmed residual tumor in 37 of 208 women [FNR, 17.8%; 95% confidence interval (CI), 12.8-23.7%]. Of these 37 women, 12 (32.4%) had residual DCIS only, 20 (54.1%) had minimal residual tumor (<5 mm), and 19 of 25 (76.0%) exhibited invasive cancer cellularity of ≤10%. In 19 of the 37 cases (51.4%), the false-negative result was potentially avoidable. Exploratory analysis showed that performing VAB with the largest needle by volume (7-gauge) resulted in no false-negative results and that combining imaging and image-guided VAB into a single diagnostic test lowered the FNR to 6.2% (95% CI, 3.4%-10.5%).

CONCLUSIONS

Image-guided VAB missed residual disease more often than expected. Refinements in procedure and patient selection seem possible and necessary before omitting breast surgery.

Curcumin as an Enhancer of Therapeutic Efficiency of Chemotherapy Drugs in Breast Cancer

Female breast cancer is the world’s most prevalent cancer in 2020. Chemotherapy still remains a backbone in breast cancer therapy and is crucial in advanced and metastatic breast cancer treatment. The clinical efficiency of chemotherapy regimens is limited due to tumor heterogeneity, chemoresistance, and side effects. Chemotherapeutic drug combinations with natural products hold great promise for enhancing their anticancer efficacy. Curcumin is an ideal chemopreventive and chemotherapy agent owning to its multitargeting function on various regulatory molecules, key signaling pathways, and pharmacological safety. This review aimed to elucidate the potential role of curcumin in enhancing the efficacy of doxorubicin, paclitaxel, 5-fluorouracil, and cisplatin via combinational therapy. Additionally, the molecular mechanisms underlying the chemosensitizing activity of these combinations have been addressed. Overall, based on the promising therapeutic potential of curcumin in combination with conventional chemotherapy drugs, curcumin is of considerable value to develop as an adjunct for combination chemotherapy with current drugs to treat breast cancer. Furthermore, this topic may provide the frameworks for the future research direction of curcumin–chemotherapy combination studies and may benefit in the development of a novel therapeutic strategy to maximize the clinical efficacy of anticancer drugs while minimizing their side effects in the future breast cancer treatment.

De-escalating Surgery Among Patients with HER2 + and Triple Negative Breast Cancer

Purpose of Review

De-escalation of surgery has been central in the evolution of multidisciplinary management of breast cancer. Advances in oncology and increasing use of neoadjuvant chemotherapy (NACT) have opened opportunities for further surgical de-escalation especially for HER2 + and triple negative (TN) disease. The aim of this review is to discuss the recent data on de-escalation of surgery as well as the future directions.

Recent Findings

Patients with TN and HER2 + breast cancer with excellent response to NACT would be the ideal candidates for surgical de-escalation. Post-NACT image-guided biopsy, potentially combined with machine learning algorithms, may accurately identify patients achieving pathologic complete response that would be eligible for clinical trials assessing safety of omission of breast and axillary surgery.

Summary

Multidisciplinary research is required to further support results of preliminary studies. Current data point towards a future when even less or no surgery may be required for exceptional responders.

Hyperpolarized Carbon-13 MRI for Early Response Assessment of Neoadjuvant Chemotherapy in Breast Cancer Patients

Hyperpolarized 13C-MRI is an emerging tool for probing tissue metabolism by measuring 13C-label exchange between intravenously injected hyperpolarized [1-13C]pyruvate and endogenous tissue lactate. Here, we demonstrate that hyperpolarized 13C-MRI can be used to detect early response to neoadjuvant therapy in breast cancer. Seven patients underwent multiparametric 1H-MRI and hyperpolarized 13C-MRI before and 7-11 days after commencing treatment. An increase in the lactate-to-pyruvate ratio of approximately 20% identified three patients who, following 5-6 cycles of treatment, showed pathological complete response. This ratio correlated with gene expression of the pyruvate transporter MCT1 and lactate dehydrogenase A (LDHA), the enzyme catalyzing label exchange between pyruvate and lactate. Analysis of approximately 2,000 breast tumors showed that overexpression of LDHA and the hypoxia marker CAIX was associated with reduced relapse-free and overall survival. Hyperpolarized 13C-MRI represents a promising method for monitoring very early treatment response in breast cancer and has demonstrated prognostic potential. SIGNIFICANCE: Hyperpolarized carbon-13 MRI allows response assessment in patients with breast cancer after 7-11 days of neoadjuvant chemotherapy and outperformed state-of-the-art and research quantitative proton MRI techniques.

Innovative Standards in Surgery of the Breast after Neoadjuvant Systemic Therapy

BACKGROUND

The goal of neoadjuvant systemic therapy (NST) in breast cancer is to downstage tumors and downgrade treatment. Indications are constantly evolving. These changes raise practical questions for planning of surgery after NST.

SUMMARY

In this review we discuss current evolving aspects of surgery of the breast after NST. Breast-conserving surgery (BCS) eligibility increases after NST - both neoadjuvant chemotherapy (NAC) and neoadjuvant endocrine therapy. Adequate margin width in NST and upfront surgery are similar - "no tumor on ink" for invasive cancer. Oncoplastic breast surgery after NST is feasible - both for BCS and mastectomy with reconstruction. There is increasing interest in the possibility of omitting surgery in patients with a complete response to NAC. Several trials are being conducted in aim of achieving acceptable prediction of pathological complete response, by combination of imaging and percutaneous biopsy of the tumor bed, as well as assessing the safety of such an approach.

KEY MESSAGES

Surgery of the breast after NST should be determined not only according to biologic and anatomic parameters at diagnosis, but is dynamic, and must be tailored according to the response to therapy. The omission of surgery in exceptional responders after NAC is being explored.