Outcomes of sentinel node biopsy according to MRI response in an association with the subtypes in cN1-3 breast cancer after neoadjuvant systemic therapy, multicenter cohort study.

BACKGROUND: This study investigated the feasibility of sentinel lymph node biopsy (SLNB) after neoadjuvant systemic therapy (NAST) in patients with initially high nodal burden. METHODS: In the multicenter retrospective cohort, 388 individuals with cN1-3 breast cancer who underwent NAST and had SLNB followed by completion axillary lymph node dissection were included. In an external validation cohort, 267 patients with HER2+ or triple-negative breast cancer (TNBC) meeting similar inclusion criteria were included. Primary outcome was the false-negative rates (FNRs) of SLNB according to the MRI response and subtypes. We defined complete MRI responders as patients who experienced disappearance of suspicious features in the breast and axilla after NAST. RESULTS: In the multicenter retrospective cohort, 130 (33.5%) of 388 patients were of cN2-3, and 55 (14.2%) of 388 patients showed complete MRI responses. In hormone receptor-positive HER2- (n = 207), complete and non-complete responders had a high FNRs (31.3% [95% CI 8.6-54.0] and 20.9% [95% CI 14.1-27.6], respectively). However, in HER2+ or TNBC (n = 181), the FNR of complete MRI responders was 0% (95% CI 0-0), whereas that of non-complete responders was 33.3% (95% CI 20.8-45.9). When we validated our findings in the external cohort with HER2+ or TNBC (n = 267), of which 34.2% were cN2-3, the FNRs of complete were 7.1% (95% CI 0-16.7). CONCLUSIONS: Our findings suggest that SLNB can be a reliable option for nodal status evaluation in selected patients who have responded well to NAST, especially in HER2+ and TNBC patients who show a complete MRI response.

Micrometastases in axillary lymph nodes in breast cancer, post-neoadjuvant systemic therapy.

INTRODUCTION: The significance of minimal residual axillary disease, specifically micrometastases, following neoadjuvant systemic therapy (NST) remains largely unexplored. Our study aimed to elucidate the prognostic implications of micrometastases in axillary and sentinel lymph nodes following NST. METHODS: This retrospective study analyzed primary breast cancer patients who underwent surgery after NST from September 2006 through February 2018. All patients received axillary lymph node dissection (ALND), either with or without sentinel lymph node biopsy. Recurrence-free survival (RFS)-associated variables were identified using a multivariate Cox proportional hazard model. RESULTS: Of the 978 patients examined, 438 (44.8%) exhibited no pathologic lymph node involvement (ypN0) after NST, while 89 (9.1%) had micrometastases (ypN1mi) and 451 (46.7%) had macrometastases (ypN+). Notably, 51.1% of the patients with sentinel lymph node micrometastases (SLNmi) had additional metastases, nearly triple that of SLN-negative patients (P < 0.001), and 29.8% of SLNmi patients were upstaged with the ALND. Although ypN1mi was not associated with RFS in patients post-NST (HR, 1.02; 95% CI, 0.42-2.49; P = 0.958), SLNmi patients experienced significantly worse RFS compared to SLN-negative patients (hazard ratio [HR], 2.23; 95% confidence intervals [CI], 1.12-4.46; P = 0.023). Additional metastases in SLNmi were more prevalent in patients with larger residual breast disease greater than 20 mm, HR-positive/HER2-negative subtype, and low Ki-67 LI (< 14%). CONCLUSIONS: SLNmi is a negative prognostic factor significantly associated with additional non-SLN metastases, while ypN1mi does not influence the prognosis compared to ypN0. Hence, additional ALND may be warranted to confirm axillary nodal status in patients with SLNmi.

Reliability of Magseed® marking before neoadjuvant systemic therapy with subsequent contrast-enhanced mammography in patients with non-palpable breast cancer lesions after treatment: the MAGMA study.

PURPOSE: To assess the reliability of excising residual breast cancer lesions after neoadjuvant systemic therapy (NAST) using a previously localized paramagnetic seed (Magseed®) and the subsequent use of contrast-enhanced spectral mammography (CESM) to evaluate response. METHODS: Observational, prospective, multicenter study including adult women (> 18 years) with invasive breast carcinoma undergoing NAST between January 2022 and February 2023 with non-palpable tumor lesions at surgery. Radiologists marked tumors with Magseed® during biopsy before NAST, and surgeons excised tumors guided by the Sentimag® magnetometer. CESMs were performed before and after NAST to evaluate tumor response (Response Evaluation Criteria for Solid Tumors [RECIST]). We considered intraoperative, surgical, and CESM-related variables and histological response. RESULTS: We analyzed 109 patients (median [IQR] age of 55.0 [46.0, 65.0] years). Magseed® was retrieved from breast tumors in all surgeries (100%; 95% CI 95.47-100.0%) with no displacement and was identified by radiology in 106 patients (97.24%), a median (IQR) of 176.5 (150.0, 216.3) days after marking. Most surgeries (94.49%) were conservative; they lasted a median (IQR) of 22.5 (14.75, 40.0) min (95% CI 23.59-30.11 min). Most dissected tumor margins (93.57%) were negative, and few patients (5.51%) needed reintervention. Magseed® was identified using CESM in all patients (100%); RECIST responses correlated with histopathological evaluations of dissected tumors using the Miller-Payne response grade (p < 0.0001) and residual lesion diameter (p < 0.0001). Also 69 patients (63.3%) answered a patient's satisfaction survey and 98.8% of them felt very satisfied with the entire procedure. CONCLUSION: Long-term marking of breast cancer lesions with Magseed® is a reliable and feasible method in patients undergoing NAST and may be used with subsequent CESM.

Breast surgery after neoadjuvant chemotherapy in patients with lobular carcinoma: surgical and oncologic outcome.

INTRODUCTION: Breast cancer patients with invasive lobular carcinoma (ILC) have an increased risk of positive margins after surgery and often show little response to neoadjuvant chemotherapy (NAC). We aimed to investigate surgical outcomes in patients with ILC treated with NAC. METHODS: In this retrospective cohort study, all breast cancer patients with ILC treated with NAC who underwent surgery at the Netherlands Cancer Institute from 2010 to 2019 were selected. Patients with mixed type ILC in pre-NAC biopsies were excluded if the lobular component was not confirmed in the surgical specimen. Main outcomes were tumor-positive margins and re-excision rate. Associations between baseline characteristics and tumor-positive margins were assessed, as were complications, locoregional recurrence rate (LRR), recurrence-free survival (RFS), and overall survival (OS). RESULTS: We included 191 patients. After NAC, 107 (56%) patients had breast conserving surgery (BCS) and 84 (44%) patients underwent mastectomy. Tumor-positive margins were observed in 67 (35%) patients. Fifty five (51%) had BCS and 12 (14%) underwent mastectomy (p value < 0.001). Re-excision was performed in 35 (33%) patients with BCS and in 4 (5%) patients with mastectomy. Definitive surgery was mastectomy in 107 (56%) patients and BCS in 84 (44%) patients. Tumor-positive margins were associated with cT ≥ 3 status (OR 4.62, 95% CI 1.26-16.98, p value 0.021) in the BCS group. Five-year LRR (4.7%), RFS (81%), and OS (93%) were not affected by type of surgery after NAC. CONCLUSION: Although 33% of ILC breast cancer patients undergoing BCS after NAC required re-excision for positive resection margins, it is considered safe given that five-year RFS remained excellent and LRR and OS did not differ by extent of surgery.

Use of neoadjuvant paclitaxel in breast angiosarcoma-Impact on surgical resection and response rates.

OBJECTIVE: Breast angiosarcoma is a tumor that can arise as a primary breast tumor or in association with prior radiation therapy. Angiosarcomas are uniquely sensitive to paclitaxel. This study evaluated the impact neoadjuvant paclitaxel (NAC) therapy has on surgical outcomes, tumor recurrence, and survival in breast angiosarcomas. METHODS: Patients with angiosarcoma of the breast, either primary or radiation-associated, were identified from a prospective institutional database. Patients receiving NAC were compared to those treated with upfront surgery. Clinical and pathological variables were compared using Student's t-test or Fisher's exact test, differences in survival were calculated using Kaplan-Meier methods. RESULTS: Twenty-four patients with angiosarcoma of the breast were identified, 10 with primary angiosarcoma and 14 with radiation-associated angiosarcoma. Twelve patients received NAC, 6 of each with primary angiosarcoma or radiation-associated angiosarcoma. Of these 12 patients, 11 had a margin negative resection (91%) of which, nine had a complete pathological response on surgical pathology. Of the 12 surgery-first patients, four (n = 4/12, 33%) had positive surgical margins, two of the four underwent reoperation. With a median follow-up of 16 months, four NAC patients had recurrence (33%) compared to six patients in the surgery-first group (58%) (p = 0.41). While not statistically significant, NAC patients had a 33% less risk of recurring compared to surgery-first patients ([hazard ratio =0.67 (95% confidence interval 0.16-2.72; p = 0.6]). CONCLUSION: NAC for breast angiosarcoma may be associated with high rates of complete pathological response and margin-negative resection. However, this did not impact overall survival. Future prospective control studies and longer follow-up periods are warranted to understand the impact on recurrence and survival.

Axillary Management: How Much Is Too Much?

PURPOSE OF REVIEW: To review the current management of the axilla in breast cancer. RECENT FINDINGS: Axillary dissection is no longer indicated in patients with clinically node-negative axilla with 1-2 positive sentinel lymph nodes following upfront surgery or in patients with clinically node-negative axilla following neoadjuvant chemotherapy. Breast cancer has evolved away from routine axillary clearance to the less invasive sentinel lymph node biopsy to now complete omission of axillary sampling in select patients. We will review the most salient evidence that has shaped these practice changes over the last three decades. Current practice controversies are especially relevant for elderly populations and those receiving neoadjuvant therapy. Ongoing clinical trials will provide data to further guide breast cancer surgical management.

Clinical impact of MRI-detected additional lesions in breast cancer patients with neoadjuvant systemic therapy at the Netherlands cancer institute.

BACKGROUND: In breast cancer patients treated with neoadjuvant systemic therapy (NST), MRI is used pre- and post-NST for response monitoring. The relevance of additional MRI-detected lesions in these patients is unclear. Therefore, we aimed to assess the impact of pre-NST MRI-detected additional lesions on surgical treatment and outcome. METHODS: We retrospectively selected all early-stage breast cancer patients with MRI pre-NST at our institute from January 2010-2015. MRI-detected lesions were defined as separated from the index tumor and occult at conventional mammography and ultrasound. Outcomes were change in surgical treatment and five-year recurrence-free and overall survival. RESULTS: Overall, MRI detected additional lesions in 206 (31%) of 656 patients: in 160 patients in the ipsilateral breast and in 78 contralateral breasts, including 32 bilateral cases. Ipsilateral lesions were mostly categorized BI-RADS 5 (54 %) and contralateral lesions BI-RADS 3 (64%). Targeted ultrasound was performed in 115 (56%) patients: in 70 ipsilateral and in 64 contralateral cases. Biopsy was obtained in 44 (28% of 160) ipsilateral and 50 (64% of 78) contralateral breasts, containing tumor foci in 20 (13% of 160) and 11 (14% of 78) cases, respectively. Surgical treatment changed in 54 (26% of 206) patients: 19 (9%) had mastectomy, 24 (12%) had wider local excision and 11 (5%) underwent contralateral surgery. Five-year recurrence-free and overall survival did not differ for patients with local excision or mastectomy. CONCLUSION: Pre-NST MRI-detected additional lesions in 31% of patients, resulting in more extensive surgery in 26% of these patients, including 5% contralateral surgeries.

De-ESCAlating RadioTherapy in breast cancer patients with pathologic complete response to neoadjuvant systemic therapy: DESCARTES study.

PURPOSE: Neoadjuvant systemic therapy (NST) is increasingly used in breast cancer patients and depending on subtype, 10-89% of patients will attain pathologic complete response (pCR). In patients with pCR, risk of local recurrence (LR) after breast conserving therapy is low. Although adjuvant radiotherapy after breast conserving surgery (BCS) reduces LR further in these patients, it may not contribute to overall survival. However, radiotherapy may cause early and late toxicity. The aim of this study is to show that omission of adjuvant radiotherapy in patients with a pCR after NST will result in acceptable low LR rates and good quality of life. METHODS: The DESCARTES study is a prospective, multicenter, single arm study. Radiotherapy will be omitted in cT1-2N0 patients (all subtypes) who achieve a pCR of the breast and lymph nodes after NST followed by BCS plus sentinel node procedure. A pCR is defined as ypT0N0 (i.e. no residual tumor cells detected). Primary endpoint is the 5-year LR rate, which is expected to be 4% and deemed acceptable if less than 6%. In total, 595 patients are needed to achieve a power of 80% (one-side alpha of 0.05). Secondary outcomes include quality of life, Cancer Worry Scale, disease specific and overall survival. Projected accrual is five years. CONCLUSION: This study bridges the knowledge gap regarding LR rates when adjuvant radiotherapy is omitted in cT1-2N0 patients achieving pCR after NST. If the results are positive, radiotherapy may be safely omitted in selected breast cancer patients with a pCR after NST. TRIAL REGISTRATION: This study is registered at ClinicalTrials.gov on June 13th 2022 (NCT05416164). Protocol version 5.1 (15-03-2022).

Trends in use of neoadjuvant systemic therapy in patients with clinically node-positive breast cancer in Europe: prospective TAXIS study (OPBC-03, SAKK 23/16, IBCSG 57-18, ABCSG-53, GBG 101).

PURPOSE: The aim of this study was to evaluate clinical practice heterogeneity in use of neoadjuvant systemic therapy (NST) for patients with clinically node-positive breast cancer in Europe. METHODS: The study was preplanned in the international multicenter phase-III OPBC-03/TAXIS trial (ClinicalTrials.gov Identifier: NCT03513614) to include the first 500 randomized patients with confirmed nodal disease at the time of surgery. The TAXIS study's pragmatic design allowed both the neoadjuvant and adjuvant setting according to the preferences of the local investigators who were encouraged to register eligible patients consecutively. RESULTS: A total of 500 patients were included at 44 breast centers in six European countries from August 2018 to June 2022, 165 (33%) of whom underwent NST. Median age was 57 years (interquartile range [IQR], 48-69). Most patients were postmenopausal (68.4%) with grade 2 and 3 hormonal receptor-positive and human epidermal growth factor receptor 2-negative breast cancer with a median tumor size of 28 mm (IQR 20-40). The use of NST varied significantly across the countries (p < 0.001). Austria (55.2%) and Switzerland (35.8%) had the highest percentage of patients undergoing NST and Hungary (18.2%) the lowest. The administration of NST increased significantly over the years (OR 1.42; p < 0.001) and more than doubled from 20 to 46.7% between 2018 and 2022. CONCLUSION: Substantial heterogeneity in the use of NST with HR+/HER2-breast cancer exists in Europe. While stringent guidelines are available for its use in triple-negative and HER2+ breast cancer, there is a need for the development of and adherence to well-defined recommendations for HR+/HER2-breast cancer.

Nanoparticle albumin-bound paclitaxel-based neoadjuvant regimen: A promising treatment option for HER2-low-positive breast cancer.

This study aimed to compare the efficacy of neoadjuvant systemic therapy (NST) with solvent-based paclitaxel (Sb-P), liposomal paclitaxel (Lps-P), nanoparticle albumin-bound paclitaxel (Nab-P), and docetaxel in human epidermal growth factor receptor 2 (HER2)-low-positive and HER2-zero breast cancers. A total of 430 patients receiving 2-weekly dose-dense epirubicin and cyclophosphamide (EC) followed by 2-weekly paclitaxel (Sb-P, Lps-P, or Nab-P), or 3-weekly EC followed by 3-weekly docetaxel for NST were enrolled in the study. In HER2-low-positive patients, the pathological complete response (pCR) rate in Nab-P group was significantly higher than that in the other three paclitaxel groups (2.8 % in Sb-P group, 4.7 % in Lps-P group, 23.2 % in Nab-P group and 3.2 % in docetaxel group, p < 0.001). In HER2-zero patients, the pCR rate did not differ significantly among the four paclitaxel groups (p = 0.278). The NST regimen containing Nab-P could be considered a promising treatment option in HER2-low-positive breast cancer.

Neoadjuvant systemic therapy in geriatric breast cancer patients: a National Cancer Database (NCDB) analysis.

PURPOSE: Neoadjuvant systemic therapy (NAST) can be an effective treatment option for patients with HER2 + or triple negative breast cancer (TNBC). However, its use in geriatric patients is largely understudied. Our aim is to investigate the effect of NAST in both septuagenarians and octogenarians with HER2 + or TNBC to better understand its role in the geriatric patient population. METHODS: We utilized the National Cancer Database (NCDB) to analyze female patients with HER2 + or TNBC between 70 and 89 years. We compared the baseline demographic and clinical characteristics of septuagenarians and octogenarians using mixed-effect modeling for continuous variables and conditional logistic regressions for categorical variables. Overall survival (OS) between several subgroups was compared based on a propensity score model. Kaplan-Meier method was used to calculate OS between the subgroups, and log-rank test was used to compare OS results. RESULTS: A total of 16,443 patients met inclusion/exclusion criteria, of which 92.9% had infiltrative ductal carcinoma and 73.5% were TNBC. Most patients received NAST as a first course of therapy (58.8%). Septuagenarians were more likely to receive NAST (65.9%), whereas octogenarians were more likely to receive upfront surgical resection (67.7%). Our analysis demonstrated OS benefit with NAST among patients who received surgical resection. However, in patients who received NAST, decline during therapy was associated with a significantly poorer OS outcomes in general. CONCLUSION: When combined with surgical resection, NAST is an effective treatment option in both septuagenarians and octogenarians. Nonetheless, careful selection of NAST recipients in this population remains critical to optimize patient outcome.

Early ultrasound evaluation identifies excellent responders to neoadjuvant systemic therapy among patients with triple-negative breast cancer.

BACKGROUND: Heterogeneity exists in the response of triple-negative breast cancer (TNBC) to standard anthracycline (AC)/taxane-based neoadjuvant systemic therapy (NAST), with 40% to 50% of patients having a pathologic complete response (pCR) to therapy. Early assessment of the imaging response during NAST may identify a subset of TNBCs that are likely to have a pCR upon completion of treatment. The authors aimed to evaluate the performance of early ultrasound (US) after 2 cycles of neoadjuvant NAST in identifying excellent responders to NAST among patients with TNBC. METHODS: Two hundred fifteen patients with TNBC were enrolled in the ongoing ARTEMIS (A Robust TNBC Evaluation Framework to Improve Survival) clinical trial. The patients were divided into a discovery cohort (n = 107) and a validation cohort (n = 108). A receiver operating characteristic analysis with 95% confidence intervals (CIs) and a multivariate logistic regression analysis were performed to model the probability of a pCR on the basis of the tumor volume reduction (TVR) percentage by US from the baseline to after 2 cycles of AC. RESULTS: Overall, 39.3% of the patients (42 of 107) achieved a pCR. A positive predictive value (PPV) analysis identified a cutoff point of 80% TVR after 2 cycles; the pCR rate was 77% (17 of 22) in patients with a TVR ≥ 80%, and the area under the curve (AUC) was 0.84 (95% CI, 0.77-0.92; P < .0001). In the validation cohort, the pCR rate was 44%. The PPV for pCR with a TVR ≥ 80% after 2 cycles was 76% (95% CI, 55%-91%), and the AUC was 0.79 (95% CI, 0.70-0.87; P < .0001). CONCLUSIONS: The TVR percentage by US evaluation after 2 cycles of NAST may be a cost-effective early imaging biomarker for a pCR to AC/taxane-based NAST.

Enhanced axillary assessment using intradermally injected microbubbles and contrast-enhanced ultrasound (CEUS) before neoadjuvant systemic therapy (NACT) identifies axillary disease missed by conventional B-mode ultrasound that may be clinically relevant.

PURPOSE: The purpose of this study is to measure pre-treatment diagnostic yield of malignant lymph nodes (LN) using contrast-enhanced ultrasound (CEUS) in addition to B-mode axillary ultrasound and compare clinicopathological features, response to NACT and long-term outcomes of patients with malignant LN detected with B-mode ultrasound versus CEUS. METHODS: Between August 2009 and October 2016, NACT patients were identified from a prospective database. Follow-up data were collected until May 2019. RESULTS: 288 consecutive NACT patients were identified; 77 were excluded, 110 had malignant LN identified by B-mode ultrasound (Group A) and 101 patients with negative B-mode axillary ultrasound had CEUS with biopsy of sentinel lymph nodes (SLN). In two cases CEUS failed. Malignant SLN were identified in 35/99 (35%) of B-mode ultrasound-negative cases (Group B). Patients in Group A were similar to those in Group B in age, mean diagnostic tumour size, grade and oestrogen receptor status. More Group A patients had a ductal phenotype. In the breast, 34 (31%) Group A patients and 8 (23%) Group B patients achieved a pathological complete response (PCR). In the axilla, 41 (37%) and 13 (37%) Groups A and B patients, respectively, had LN PCR. The systemic relapse rate was not statistically different (5% and 16% for Groups A and B, respectively). CONCLUSIONS: Enhanced assessment with CEUS before NACT identifies patients with axillary metastases missed by conventional B-mode ultrasound. Without CEUS, 22 (63%) of cases in Group B (negative B-mode ultrasound) may have been erroneously classed as progressive disease by surgical SLN excision after NACT.

Surgical Management of the Axilla of HER2+ Breast Cancer in the Z1071 Era: A Propensity-Score-Matched Analysis of the NCDB.

INTRODUCTION: We aim to analyze survival outcomes for sentinel lymph node biopsy (SLNB) versus axillary lymph node dissection (ALND) in human epidermal growth factor receptor (HER2)+ infiltrative ductal carcinoma (IDC) that demonstrate complete clinical response (cCR) to neoadjuvant systemic therapy (NAST) after initial presentation with clinical N1 (cN1) disease. METHODS: NCDB 2004-2017 was utilized for the analysis. Female patients with unilateral HER2+ IDC, stage cT1-T4 cN1, who demonstrated cCR to NAST with reported definitive axillary surgical management were included. Patients were propensity score matched, and overall survival (OS) was compared. Cox regression analysis was used to identify survival predictors. RESULTS: 6453 patients were selected, of whom 2461 (38.1%) had SLNB and 3992 (69.1%) had ALND as definitive axillary surgical management. The trend of SLNB utilization increased from 20% in 2012 to 50% in 2017. A total of 2454 patients were matched from each group with adequate adjustment for all variables. There was no difference in OS between SLNB versus ALND (84.03 ± 0.36 versus 84.62 ± 0.42 months; p = 0.522). Cox regression identified age, cT stage, primary tumor response to NAST, ypN+, and endocrine therapy as significant OS predictors. In subgroup analysis of patients with ypN+ who had SLNB as a definitive procedure, primary tumor response to NAST and continuation of adjuvant chemotherapy were associated with improved OS. CONCLUSION: In cN1 HER2+ IDC patients who demonstrate cCR to NAST, SLNB is a reasonable definitive procedure for axillary management with comparable OS outcomes to ALND. However, higher-level data are required to determine the appropriate management in the case of ypN+.

Eliminating the breast cancer surgery paradigm after neoadjuvant systemic therapy: current evidence and future challenges.

In patients with operable early breast cancer, neoadjuvant systemic treatment (NST) is a standard approach. Indications have expanded from downstaging of locally advanced breast cancer to facilitate breast conservation, to in vivo drug-sensitivity testing. The pattern of response to NST is used to tailor systemic and locoregional treatment, that is, to escalate treatment in nonresponders and de-escalate treatment in responders. Here we discuss four questions that guide our current thinking about 'response-adjusted' surgery of the breast after NST. (i) What critical diagnostic outcome measures should be used when analyzing diagnostic tools to identify patients with pathologic complete response (pCR) after NST? (ii) How can we assess response with the least morbidity and best accuracy possible? (iii) What oncological consequences may ensue if we rely on a nonsurgical-generated diagnosis of, for example, minimally invasive biopsy proven pCR, knowing that we may miss minimal residual disease in some cases? (iv) How should we design clinical trials on de-escalation of surgical treatment after NST?

ΔKi67 proliferation index as independent predictive and prognostic factor of outcome in luminal breast cancer: data from neoadjuvant letrozole-based treatment.

A key tool for monitoring breast cancer patients under neoadjuvant treatment is the identification of reliable predictive markers. Ki67 has been identified as a prognostic and predictive marker in ER-positive breast cancer. Ninety ER-positive, HER2 negative locally advanced breast cancer patients received letrozole (2.5 mg daily) and cyclophosphamide (50 mg daily) with/without Sorafenib (400 mg/bid daily) for 6 months before undergoing surgery. Ki67 expression and tumor size measured with caliber were determined at baseline, after 30 days of treatment and at the end of treatment. Patients were assigned to a clinical response category according to Response Evaluation Criteria in Solid Tumors, both at 30 days and before surgery and further classified as high-responder and low-responder according to the median variation of Ki67 values between biopsy and 30 days and between biopsy and surgery time. The predictive role of Ki67 and its changes with regard to clinical response and survival was analyzed. No differences in terms of survival outcomes emerged between the arms of treatment, while we observed a higher percentage of women with progression or stable disease in arm with the combination containing Sorafenib (20.5% vs 7.1%, p = 0.06). Clinical complete responders experienced a greater overall variation in Ki67 when compared with partial responders and patients with progressive/stable disease (66.7% vs 30.7%, p = 0.009). High responders showed a better outcome than low responders in terms of both disease-free survival (p = 0.009) and overall survival (p = 0.002). ΔKi67 score evaluated between basal and residual tumor at definitive surgery showed to be highly predictive of clinical complete response, and a potential parameter to be used for predicting disease-free survival and overall survival in luminal breast cancer treated with neoadjuvant endocrine-based therapy.

Breast Cancer Outcomes of Neoadjuvant Versus Adjuvant Chemotherapy by Receptor Subtype: A Scoping Review.

BACKGROUND: Trials demonstrate equivalent survival for breast cancers treated with neoadjuvant chemotherapy (NAC) or adjuvant chemotherapy (AC). However, these were conducted before the recognition of the importance of receptor subtype for survival and chemotherapy response. Therefore, chemotherapy timing may impact survival for certain receptor subtypes. A scoping review of studies assessing outcomes by chemotherapy timing based on receptor subtype was conducted to evaluate gaps in the existing literature. METHODS: Three databases were searched in February 2019 with terms related to breast cancer, NAC/AC, and survival. Inclusion criteria were original peer-reviewed studies published in English after 1989 comparing breast cancer outcomes for females based on chemotherapy timing. Studies/sections of studies lacking outcomes by receptor subtype or including patients missing appropriate targeted therapy were excluded. RESULTS: Of 7354 articles, 262 abstracts and 60 full texts were reviewed. Three studies met criteria. All were single-institution retrospective studies analyzing outcomes for triple negative (TN) patients with one study also examining luminal A patients. Significant differences in clinical characteristics existed between patients selected for NAC versus AC. Two studies demonstrated no survival difference by chemotherapy timing for TN patients, with the third showing improved likelihood of survival after AC for TN patients. No difference was seen for patients with luminal A cancer. CONCLUSIONS: Our scoping review reveals a significant gap in the existing literature regarding optimal timing of chemotherapy for modern-era patients receiving targeted therapy based on receptor subtype. Review of the identified studies identified methodological challenges to answering this question through observational study designs.

Management of the Axilla after Neoadjuvant Systemic Therapy.

OPINION STATEMENT: As the use of neoadjuvant systemic therapy (NAST) increases, the optimal management of the axilla has become increasingly complex. Consensus among professional organizations is that those patients with clinically negative axillary nodes who are being considered for NAST should undergo a sentinel lymph node (SLN) biopsy following NAST. If a positive SLN is subsequently identified, an axillary lymph node dissection (ALND) is the current standard of care. For patients with clinically node-positive disease, SLN biopsy is a reasonable option for those with a good response to NAST. Patients should undergo SLN mapping with a dual dye technique. Additionally, at least 2 lymph nodes should be removed, including the previously biopsied and marked lymph node with cancer. In this setting, the identification and false negative rates are acceptable. Patients found to have a negative SLN at this time may be spared the morbidity associated with ALND. Patients found to have persistently positive lymph nodes following NAST, either clinically or pathologically, should undergo a complete ALND.

Pathologic complete response rate according to HER2 detection methods in HER2-positive breast cancer treated with neoadjuvant systemic therapy.

PURPOSE: Human epidermal growth factor receptor 2 (HER2)-positive breast cancers are known to have significant clinical and pathological response to neoadjuvant systemic therapy (NST). The aim of this study was to identify factors associated with pathological complete response (pCR), defined as no residual invasive carcinoma in the breast and axillary lymph nodes (ypT0/is ypN0), among patients with HER2-positive breast cancer and to compare pCR rates between breast cancers with HER2 protein overexpression by immunohistochemistry (IHC) versus HER2 gene amplification by fluorescence in situ hybridization (FISH) in the absence of protein overexpression by IHC. METHODS: We conducted a retrospective review of HER2-positive breast cancer patients treated with NST and surgery at Memorial Sloan Kettering Cancer Center between January 2013 and May 2018. Estrogen receptor (ER), progesterone receptor (PR), and HER2 status were assessed according to the 2018 ASCO/CAP guidelines. RESULTS: During the study period, 560 patients were identified. Of 531 patients with IHC results available, 455 patients had HER2 IHC 3+, and 76 had IHC < 3+ but HER2 amplification detected by FISH. The overall pCR rate was 59% (330/560). The pCR rate among patients with HER2 protein overexpression (IHC 3+) was 67%, compared to 17% among patients with HER2 amplification by FISH (IHC < 3+). On univariate and multivariate analyses, HER2 protein overexpression by IHC (IHC 3+) was a significant predictor of pCR, along with grade 3 histology, PR-negative status, and dual anti-HER2 therapy. CONCLUSION: Although both HER2 IHC and FISH are standard HER2 testing methods in breast cancer, achievement of pCR is associated with HER2 IHC expression level, among other factors.

Assessment of sentinel lymph node biopsy after neoadjuvant chemotherapy for breast cancer in two subgroups: Initially node negative and node positive converted to node negative - A systemic review and meta-analysis.

BACKGROUND: Neoadjuvant chemotherapy (NAC) is increasingly used to treat patients with breast cancer, but the reliability of sentinel lymph node biopsy (SLNB) following chemotherapy is in doubt. In this meta-analysis, we aimed to evaluate studies that examine the results of SLNB after NAC to assess identification rate (IR) and false-negative rate (FNR). MATERIALS AND METHODS: Systemic searches were performed in the PubMed, ISI Web of Sciences, Scopus, and Cochrane databases from January 1, 2000, to November 30, 2016, for studies of SLNB after NAC for breast cancer and followed by axillary lymph node (LN) dissection in two subgroups: initially node negative and node positive converted to node negative. Two reviewers independently review quality of included studies. A random-effects model was used to pool IR and FNR with 95% confidence intervals (CI), and heterogeneity among studies was assessed by I 2 and Q-test. RESULTS: A total of 23 studies with 1521 patients in the initially node-negative subgroup and 13 studies with 1088 patients in the node-positive converted to node-negative subgroup, were included in this meta-analysis with IR and FNR of 94% (95% CI: 92-96) and 7% (95% CI: 5-9) in the initially node-negative subgroup and 89% (95% CI: 85-94) and 13% (95% CI: 7-18) in the node-positive converted to node-negative subgroup, respectively. CONCLUSION: Our meta-analysis showed acceptable IR and FNR in initially node-negative group and it seems feasible in these patients, but these parameters did not reach to predefined value in node-positive converted to node-negative group, and thus, it is not recommended in these patients.