Sentinel lymph node surgery after neoadjuvant chemotherapy is accurate and reduces the need for axillary dissection in breast cancer patients

[Sentinel node and breast cancer: A state-of-the-art in 2019]

Since 1994 and Giuliano's description of sentinel lymph node technique, this procedure has considerably improved and is nowadays, one of the essential pillars in the management of breast cancer. Neoadjuvant chemotherapy (NAC) is effective on regional control, especially on axillary lymph node. Various learned societies recommend that the initial proved GS can be realized before (CNGOF 2010, Saint-Paul de Vence 2013, ESMO 2015, St-Gallen 2015, NCCN 2016) or after (ASCO 2014, ESMO 2015, Saint-Gallen 2015) CNA when the patient is considered like N0. In patients with initial lymph node involvement, GS searching it is not yet recommended. SLN detection before NAC remains an important prognostic factor especially in N+ patients before surgery. The purpose of this article was a reviewing of medical literature regarding possible indications for SLN detection and axillary dissection in patients with NAC according to sentinel lymph node status. The secondary objective was to put forward different perspectives and studies dealing with this subject. The complete pathological response appears to be an important selection criterion for proposing SLN to these patients and avoiding a "useless" AD. It is important to include patients in the trials to make recommendations progress on SLN after NAC and avoid a rate of uninjured AD.

Locally advanced breast cancer treated with neoadjuvant chemotherapy and adjuvant radiotherapy: a retrospective cohort analysis

Background

Neoadjuvant chemotherapy (NAC) is increasingly used to treat locally advanced breast cancer (LABC). Improved response to NAC correlates with better survival outcomes. The dual purpose of this study is to report recurrence and survival outcomes for LABC patients treated with NAC, surgery and adjuvant radiotherapy and to correlate these outcomes with tumour response after NAC using multiple response assessment methods.

Methods

All LABC patients treated for curative intent with NAC, surgery, and adjuvant radiotherapy at our institute between January 2009 and December 2014 were included for analysis. NAC was mostly anthracycline and taxane-based; radiotherapy consisted of 50 Gy to the breast/chest wall and regional lymph nodes. Response to NAC was categorized using synoptic pathology reports, modified-RECIST and Chevallier scores. Survival curves were generated by the Kaplan-Meier method and compared using the log-rank test.

Results

The cohort included 103 patients nearly equally divided between Stage II (n = 53) and Stage III (n = 50). Rates of locoregional control (LRC), recurrence-free survival (RFS), and overall survival (OS) were 99, 98, and 100% at 1 year and 89, 69 and 77% at 5 years, respectively. Responses to NAC did not correlate with LRC (p > 0.05) but did correlate with RFS and OS (p < 0.05), except that the Chevallier score did not predict RFS (p = 0.06). Using bivariate Cox modeling tumour size before (p = 0.003) and after (p < 0.001) NAC, stage group (p = 0.05), and response assessed by synoptic pathology (p = 0.05), modified-RECIST (p = 0.001), and Chevallier score (p = 0.015) all predicted for RFS. No factors predicted for LRC.

Conclusion

Pathologic response by all tested methods correlated with improved survival but were not associated with decreased LRC.

The Evolving and Multidisciplinary Considerations in Nodal Radiation in Breast Cancer

The therapeutic management of regional lymph nodes in breast cancer has seen a remarkable change in the past 2 decades. Clinical trials have refined our knowledge regarding the biology of the disease including the prognostic significance of disease in the regional lymph nodes. The contemporary management of lymph nodes is also influenced by advances in surgical technique, radiation oncology delivery systems, and effective systemic therapy regimens. This paper describes the role of regional nodal irradiation in the context of the de-escalation of axillary surgery, improved understanding of the molecular and pathologic features, and increasing use of neoadjuvant chemotherapy.

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.

Overview of Breast Cancer Therapy

Breast cancer treatment is multidisciplinary. Most women with early stage breast cancer are candidates for breast-conserving surgery with radiotherapy or mastectomy. The risk of local recurrence and the chance of survival does not differ with these approaches. Sentinel node biopsy is used for axillary staging, and individualized approaches are minimizing the need for axillary dissection in women with positive sentinel nodes. Adjuvant systemic therapy is used in most women based on proven survival benefit, and molecular profiling to individualize treatment based on risk is now a clinical reality for patients with hormone receptor-positive cancers.

Current Status and Future Perspectives of Axillary Management in the Neoadjuvant Setting

Axillary surgery has undergone considerable changes in recent years, especially in relation to patients who undergo neoadjuvant chemotherapy (NACT). Due to constantly decreasing rates of recurrence and death from breast cancer, modern surgical strategies aim at de-escalating the extent of local treatment and avoiding unnecessary procedures. This relates especially to lymph node surgery which is associated with considerable morbidity. In patients who initially present with clinically node-negative disease, sentinel lymph node biopsy (SLNB) is increasingly performed after NACT. The determination of the post-NACT nodal status does not only spare patients from additional surgery but also allows the assessment of pathologic complete response which is increasingly becoming an important tool for treatment planning. Since more than 70% of these patients have a ypN0 status after NACT, future trials will aim to identify patients who might be spared any axillary surgery after NACT. In patients who initially present with positive lymph nodes, the success rates of SLNB in terms of detection and accuracy are less favorable compared to those in patients who undergo primary surgery. The clinical significance of this is unclear. To reduce unnecessary axillary dissection in patients with cN1ycN0 status, prospective outcome data after SLNB without further lymph node removal are urgently needed. Improvements in surgical technique by localizing positive nodes at the time of diagnosis and removing them in a targeted surgical procedure (targeted axillary dissection) are under evaluation. Risk assessment and patient selection (including gene expression profiles) might be other ways of safely omitting axillary dissection.

Management of the axilla after neo-adjuvant chemotherapy for breast cancer: Sentinel node biopsy and radiotherapy considerations

Preoperative or neo-adjuvant chemotherapy in the management of breast cancer is a treatment approach that has gained in popularity in recent years. However, it is unclear if the treatment paradigms often employed for patients treated with surgery first hold true for those treated with preoperative chemotherapy. The role of sentinel node biopsy and the data supporting its use is different for those with clinically negative and clinically positive nodes prior to chemotherapy. For clinically node-negative patients, sentinel node biopsy after neo-adjuvant chemotherapy may be appropriate. For those node-positive patients whose axillary disease resolves clinically, the false-negative rate of the sentinel node biopsy is high. However, there are measures that can reduce that rate. After surgery, the radiation oncologist is often faced with complicated decisions surrounding the optimal radiotherapy in this setting. Tailoring radiation plans based on chemotherapy response holds promise and is the subject of ongoing clinical trials. In the accompanying article, we review the current literature on both surgery and radiation in axillary management and describe the interplay between these two treatment modalities. This highlights the need for multidisciplinary management in making treatment decisions for patients treated in this manner.

Surgical Standards for Management of the Axilla in Breast Cancer Clinical Trials with Pathological Complete Response Endpoint

Advances in the surgical management of the axilla in patients treated with neoadjuvant chemotherapy, especially those with node positive disease at diagnosis, have led to changes in practice and more judicious use of axillary lymph node dissection that may minimize morbidity from surgery. However, there is still significant confusion about how to optimally manage the axilla, resulting in variation among practices. From the viewpoint of drug development, assessment of response to neoadjuvant chemotherapy remains paramount and appropriate assessment of residual disease—the primary endpoint of many drug therapy trials in the neoadjuvant setting—is critical. Therefore decreasing the variability, especially in a multicenter clinical trial setting, and establishing a minimum standard to ensure consistency in clinical trial data, without mandating axillary lymph node dissection, for all patients is necessary. The key elements which include proper staging and identification of nodal involvement at diagnosis, and appropriately targeted management of the axilla at the time of surgical resection are presented. The following protocols have been adopted as standard procedure by the I-SPY2 trial for management of axilla in patients with node positive disease, and present a framework for prospective clinical trials and practice.

Surgical Management of Breast Cancer Treated with Neoadjuvant Therapy

Neoadjuvant therapy (NAT) allows downstaging in some cases of breast cancer. By consequence, it may enable a more conservative surgical approach or make surgery possible in cases ineligible for surgery before NAT. In this article, we review the evidence and management recommendations for optimal surgical treatment in this setting.

Sentinel node biopsy after neoadjuvant chemotherapy for breast cancer with axillary node metastasis: A survey of clinical practice

BACKGROUND

A survey of breast surgeons was conducted to evaluate changes in clinical practice regarding sentinel node biopsy (SNB) among clinically node-negative patients after neoadjuvant chemotherapy for breast cancer with axillary node metastasis.

METHODS

We conducted two surveys among 252 members of the Korean Breast Cancer Society. The questionnaire comprised a case presentation and two associated questions. The case outlined a woman diagnosed with right breast cancer; core needle biopsy had confirmed invasive ductal carcinoma and tumor size was 4 cm on imaging examination. Fine needle aspiration examination for axillary lymph node enlargement showed metastatic carcinoma. The patient underwent neoadjuvant chemotherapy and tumor size was decreased by 2 cm; axillary lymph node enlargement was not observed on palpitation or imaging examination. Finally, the patient underwent breast conserving surgery. Survey recipients were asked: 1. Would you perform SNB in this patient? 2. If you perform SNB and no axillary node metastasis is seen, would you perform additional axillary lymph node dissection (ALND)?

RESULTS

The response rate was 28.2% (71/252) and 15.1% (38/252) in 2013 and 2017, respectively. For the first question, the SNB to ALND ratio increased significantly from 54% versus 46% in 2013 to 92% versus 8% in 2017 (p < 0.001). The proportion of surgeons performing no additional ALND versus additional ALND increased from 38% versus 54% in 2013 to 53% versus 37% in 2017, but did not reach statistical significance (p = 0.1).

CONCLUSIONS

These data show that application of SNB among clinically node-negative patients after neoadjuvant chemotherapy for breast cancer with node metastasis has increased among surgeons in Korea.

Predicting Post Neoadjuvant Axillary Response Using a Novel Convolutional Neural Network Algorithm

OBJECTIVES

In the postneoadjuvant chemotherapy (NAC) setting, conventional radiographic complete response (rCR) is a poor predictor of pathologic complete response (pCR) of the axilla. We developed a convolutional neural network (CNN) algorithm to better predict post-NAC axillary response using a breast MRI dataset.

METHODS

An institutional review board-approved retrospective study from January 2009 to June 2016 identified 127 breast cancer patients who: (1) underwent breast MRI before the initiation of NAC; (2) successfully completed Adriamycin/Taxane-based NAC; and (3) underwent surgery, including sentinel lymph node evaluation/axillary lymph node dissection with final surgical pathology data. Patients were classified into pathologic complete response (pCR) of the axilla group and non-pCR group based on surgical pathology. Breast MRI performed before NAC was used. Tumor was identified on first T1 postcontrast images underwent 3D segmentation. A total of 2811 volumetric slices of 127 tumors were evaluated. CNN consisted of 10 convolutional layers, 4 max-pooling layers. Dropout, augmentation and L2 regularization were implemented to prevent overfitting of data.

RESULTS

On final surgical pathology, 38.6% (49/127) of the patients achieved pCR of the axilla (group 1), and 61.4% (78/127) of the patients did not with residual metastasis detected (group 2). For predicting axillary pCR, our CNN algorithm achieved an overall accuracy of 83% (95% confidence interval [CI] ± 5) with sensitivity of 93% (95% CI ± 6) and specificity of 77% (95% CI ± 4). Area under the ROC curve (0.93, 95% CI ± 0.04).

CONCLUSIONS

It is feasible to use CNN architecture to predict post NAC axillary pCR. Larger data set will likely improve our prediction model.

Updates in the Evaluation and Management of Breast Cancer

Breast cancer is the most commonly diagnosed cancer worldwide. More than 200,000 new cases of invasive breast cancer are diagnosed annually in the United States; approximately 40,000 patients die of the disease. The etiology of most breast cancer cases is unknown, although multiple factors predisposing to the disease have been identified. Apart from increasing age and female sex, these other factors account for only a minority of breast cancer diagnoses. This article provides an overview of the management of noninvasive and invasive breast cancer, which is often complex and varies according to patient factors, disease stage, and breast cancer subtype. Although much progress has been made, continued research endeavors are ongoing; enrollment of eligible patients in prospective clinical trials is an essential way to improve patient outcomes.

Surgical Highlights from the 40th San Antonio Breast Cancer Symposium: 5-9 December 2017, San Antonio, Texas

This year San Antonio Breast Cancer Symposium (SABCS) celebrated its 40^th anniversary. As in the past years, this year's conference was held in Henry B. Gonzalez Convention Centre, San Antonio, Texas, on 5-9 December 2017. The conference highlighted many different topic on breast cancer including basic science, translational research, local therapies, systemic therapies, survivorship, early clinical trials, and surgical topics. Even though SABCS evolved towards basic science and systemic therapy based manner in recent years, there were some important topics about local therapies and surgical approach. In this conference report, presentations and keynote talks about surgical field and local therapies will be summarised.

Axillary staging in breast cancer patients treated with neoadjuvant chemotherapy in two Dutch phase III studies

BACKGROUND

Primary aim of our study was to assess the impact of timing of sentinel node procedure, pre- versus post-neoadjuvant chemotherapy, on final pathologic node-negative rate (pN0) in patients with clinically node-negative (cN0) breast cancer. Secondary endpoint was the usability of the sentinel node procedure in patients with clinically node-positive disease that converted to cN0 after neoadjuvant chemotherapy.

PATIENTS AND METHODS

Patients were enrolled in two sequentially conducted Dutch phase III trials, studying the impact of two neoadjuvant chemotherapy schedules and use of zoledronic acid on complete pathologic response rate. For the present analyses, patients were excluded if they had not undergone surgical axillary staging.

RESULTS

In total 439 patients were included, of whom 230 (52%) had pre-treatment cN0. In this group, pN0 status was seen in 58% (N = 23) of patients with a sentinel node biopsy post-neoadjuvant chemotherapy compared to 51% (N = 83) pre-neoadjuvant chemotherapy, including the axillary lymph node dissection whenever performed. In multivariable analysis, timing of sentinel node procedure (pre- versus post- neoadjuvant chemotherapy) was, however, not significantly associated with final pN0/pN0(i+) status, with an odds ratio of 1.18 (95% CI 0.64 - 2.18) after correction for age, clinical tumor status, histology, grade, hormone- and HER2 receptor. Of patients with clinically node-positive disease only 15% had a final pN0 status, with a false-negative rate of the sentinel node of 30%.

CONCLUSION

In breast cancer patients with cN0 disease, sentinel node procedure performed post-neoadjuvant chemotherapy led to nodal down staging, although not statistically significant after multivariate correction for patient and tumor characteristics.

Total pathological complete response versus breast pathological complete response in clinical trials of reference and biosimilar trastuzumab in the neoadjuvant treatment of breast cancer

INTRODUCTION

Trastuzumab is a key drug in the neoadjuvant treatment of breast cancers that overexpress the human epidermal growth factor receptor 2 (HER2). Pathological complete response (pCR) is commonly used as an endpoint in neoadjuvant clinical trials of trastuzumab as evidence suggests it may be a surrogate for long-term survival. Several biosimilar candidates of originator or 'reference' trastuzumab are in development and have used pCR as a primary endpoint to assess therapeutic equivalence between treatments. The exact definition of pCR has varied across studies. Areas covered: Here we look at the clinical relevance of pCR and compare rates of total pCR (defined as ypT0/is ypN0) and breast pCR (defined as ypT0/is) in clinical trials of reference and biosimilar trastuzumab. Expert commentary: In order to evaluate the efficacy of neoadjuvant systemic therapies in a uniform way, standardization of trial endpoints is necessary. Future studies in HER2-positive breast cancer should include full assessment of the breast and lymph node basin before and after neoadjuvant systemic therapy, and the use of total pCR as the primary outcome.

Axillary and internal mammary sentinel lymph node biopsy in breast cancer after neoadjuvant chemotherapy

With the improvement of neoadjuvant chemotherapy (NAC), the proportion of pathological complete response (pCR) in the breast and axillary lymph node (ALN) is increasing. The evaluation of pCR does not include the status of internal mammary lymph node (IMLN). This study is to evaluate the roles of both axillary sentinel lymph node biopsy (ASLNB) and internal mammary sentinel lymph node biopsy (IM-SLNB) in breast cancer patients after NAC. There were 74 patients enrolled into this study. IM-SLNB was performed on patients with radioactive internal mammary sentinel lymph node (IM-SLN). Patients (n = 8) with cN0 and ycN0 received ASLNB, and axillary lymph node dissection (ALND) in cases of positive axillary sentinel lymph node (ASLN). Patients (n = 48) with cN+ but ycN0 received ASLNB and ALND. Patients (n = 18) with ycN+ received ALND without ASLNB. The visualization rate of IM-SLN was 56.8% (42/74). The success rate of IM-SLNB was 97.6% (41/42) and the metastasis rate of IM-SLN was 7.3% (3/41). The success rate of ASLNB was 100% (56/56). The false negative rate (FNR) of ASLNB was 17.2% (5/29). The FNR in patients with 1, 2 and ≥ 3ASLNs examined was 27.3% (3/11), 20.0% (2/10) and 0% (0/8) respectively. ASLNB could be performed on ycN0 after NAC, and ALND should be performed on initially ALN-positive patients. IM-SLNB should be considered after NAC, especially for patients with clinically positive axillary nodes before NAC, which might help make clear of the pathological nodal staging of both ALN and IMLN, improve the definition of nodal pCR, and guide the individual adjuvant regional and systemic therapy.

Evolution in sentinel lymph node biopsy in breast cancer

Sentinel lymph node biopsy (SLNB) is the standard of care for axillary staging in clinically node-negative (cN0) breast cancer patients without neoadjuvant chemotherapy (NAC). The application of SLNB in patients receiving NAC has also been explored. Evidence supports its use after NAC in pretreatment cN0 patients. Nonetheless, its routine use in all the pretreatment node-positive patients who become cN0 after NAC is unjustified due to the unacceptably high false-negative rate, which can be improved in a subset of patients. Axillary surgery omission in selected patients with a low risk of ALN metastasis has gained more and more research interest because the SLNs are tumor-free in more than 70% of all patients. To avoid drawbacks of conventional mapping methods, novel techniques for SLN detection have been developed and shown to be highly accurate in patients with early breast cancer. This article reviews the progress in SLNB in patients with breast cancer.

Tumor Biology Predicts Pathologic Complete Response to Neoadjuvant Chemotherapy in Patients Presenting with Locally Advanced Breast Cancer

BACKGROUND

Neoadjuvant chemotherapy (NAC) is used to convert patients with inoperable locally advanced breast cancer (LABC) to operability, but has not traditionally been used to avoid mastectomy or axillary dissection in this subset.

OBJECTIVE

The purpose of this study was to determine the rates of pathologic complete response (pCR) in LABC patients, and identify factors predictive of pCR to determine if responding patients might be suitable for limited surgery.

METHODS

From 2006 to 2016, 1522 patients received NAC followed by surgery; 321 had advanced disease in the breast (cT4) and/or in the nodes (cN2/N3). pCR rates were assessed by T and N stage, and receptor subtype.

RESULTS

Of 321 LABC patients, 223 were cT4, 77 were cN2, and 82 were cN3. Forty-three percent were hormone receptor (HR) positive/human epidermal growth factor receptor 2 (HER2) negative (HR+/HER2-), 23% were triple negative, and 34% were HER2+. The overall pCR rate was 25% and differed by receptor subtype (HR+/HER2- 7%, triple negative 23%, HER2+ 48%; p < 0.001). Breast pCR occurred in 27% of patients and was similar in T4 versus non-T4 disease (29% vs. 22%; p = 0.26). Nodal pCR was achieved in 38% of cN+ patients and did not differ by nodal stage (cN1 43%, cN2 36%, cN3 32%; p = 0.23). Nodal pCR was significantly more common than breast pCR (p = 0.014) across all tumor subtypes. Receptor subtype was the only predictor of overall pCR (p < 0.001).

CONCLUSION

In patients with LABC, pCR after NAC was seen in 25%, and did not differ by T or N stage. Tumor biology, but not extent of disease, predicted pCR. Studies assessing the feasibility of surgical downstaging with NAC in LABC patients are warranted.

The Optimal Treatment Plan to Avoid Axillary Lymph Node Dissection in Early-Stage Breast Cancer Patients Differs by Surgical Strategy and Tumor Subtype

BACKGROUND

Strategies to reduce the likelihood of axillary lymph node dissection (ALND) include application of Z0011 or use of neoadjuvant chemotherapy (NAC). Indications for ALND differ by treatment plan, and nodal pathologic complete response rates after NAC vary by tumor subtype. This study compared ALND rates for cT1-2N0 tumors treated with upfront surgery versus those treated with NAC.

METHODS

The ALND rates for cT1-2N0 breast cancer patients were compared by tumor subtype among women undergoing upfront surgery to NAC. Multivariable analysis with control for age, cT stage, and lymphovascular invasion, and stratification by subtype was performed.

RESULTS

The study identified 1944 cancers in 1907 women who underwent sentinel lymph node (SLN) biopsy with or without ALND (669 upfront breast-conserving surgeries [BCSs], 1004 upfront mastectomies, 271 NACs). Compared with the NAC group, the ALND rates in the BCS group were lower for estrogen receptor (ER), progesterone receptor-positive (PR+), human epidermal growth factor 2-negative (HER2-) tumors (15 vs 34%; p < 0.001). The ALND rates in the upfront mastectomy group were higher than in the NAC group for HER2+ or TN tumors. In the multivariable analysis, receipt of NAC compared with upfront BCS remained significantly associated with higher odds of ALND in the ER/PR+ HER2- subtype (hazard ratio [HR], 3.35; p < 0.001), whereas NAC versus upfront mastectomy remained significantly associated with lower odds of ALND in the HER2+ and TN subtypes (HR for HER2+, 0.19, p < 0.001; HR for TN, 0.25, p = 0.007).

CONCLUSION

The study showed that ALND rates differ according to surgery type and tumor subtype secondary to differing ALND indications and nodal response to NAC. These factors can be used to personalize treatment planning to minimize ALND risk for patients with early-stage breast cancer.

Review of the role of the sentinel node biopsy in neoadjuvant chemotherapy in women with breast cancer and negative or positive axillary node at diagnosis

The role of the selective sentinel node biopsy (SNB) is increasing in relevance in breast cancer women with indication of neoadjuvant chemotherapy (NAC). The Radiosurgery Working Group of the SEMNIM is aware of the necessity of establishing the need for SNB before or after NAC, and also how to manage patients with axillary node-negative or node-positive. There is sufficient data to assess that the SNB with radioisotope techniques are feasible and safe in all these scenarios. An adequate axilla evaluation prior to surgery and the possibility of marking prior to NAC the nodes infiltrated must be the two main pillars to guarantee the success of the SNB. It has been shown that to incorporate the SNB in breast cancer women with indication of NAC increases the rate of a conservative treatment of the axilla that will be a clear benefit for these patients.

The Neo-Bioscore Update for Staging Breast Cancer Treated With Neoadjuvant Chemotherapy: Incorporation of Prognostic Biologic Factors Into Staging After Treatment

IMPORTANCE

We previously described and validated a breast cancer staging system (CPS+EG, clinical-pathologic scoring system incorporating estrogen receptor-negative disease and nuclear grade 3 tumor pathology) for assessing prognosis after neoadjuvant chemotherapy using pretreatment clinical stage, posttreatment pathologic stage, estrogen receptor (ER) status, and grade. Development of the CPS+EG staging system predated routine administration of trastuzumab in patients with ERBB2-positive disease (formerly HER2 or HER2/neu).

OBJECTIVE

To validate the CPS+EG staging system using the new definition of ER positivity (≥1%) and to develop an updated staging system (Neo-Bioscore) that incorporates ERBB2 status into the previously developed CPS+EG.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective review of data collected prospectively from January 2005 through December 2012 on patients with breast cancer treated with neoadjuvant chemotherapy at The University of Texas MD Anderson Cancer Center.

MAIN OUTCOMES AND MEASURE

Prognostic scores were computed using 2 versions of the CPS+EG staging system, one with ER considered positive if it measured 10% or higher, the other with ER considered positive if it measured 1% or higher. Fits of the Cox proportional hazards model for the 2 sets of prognostic scores were compared using the Akaike Information Criterion (AIC). Status of ERBB2 was added to the model, and the likelihood ratio test was used to determine improvement in fit.

RESULTS

A total of 2377 patients were included; all were women (median age, 50 years [range, 21-87 years]); ER status was less than 1% in 28.9%, 1% to 9% in 8.3%, and 10% or higher in 62.8%; 591 patients were ERBB2 positive. Median follow-up was 4.2 years (range, 0.5-11.7 years). Five-year disease-specific survival was 89% (95% CI, 87%-90%). Using 1% or higher as the cutoff for ER positivity, 5-year disease-specific survival estimates determined using the CPS+EG stage ranged from 52% to 98%, thereby validating our previous finding that the CPS+EG score facilitates more refined categorization into prognostic subgroups than clinical or final pathologic stage alone. The AIC value for this model was 3333.06, while for a model using 10% or higher as the cutoff for ER positivity, it was 3333.38, indicating that the model fits were nearly identical. The improvement in fit of the model when ERBB2 status was added was highly significant, with 5-year disease-specific survival estimates ranging from 48% to 99% (P < .001). Incorporating ERBB2 into the staging system defined the Neo-Bioscore, which provided improved stratification of patients with respect to prognosis.

CONCLUSIONS AND RELEVANCE

The Neo-Bioscore improves our previously validated staging system and allows its application in ERBB2-positive patients. We recommend that treatment response and biologic markers be incorporated into the American Joint Committee on Cancer staging system.

The intraoperative assessment of sentinel nodes - Standards and controversies

Intraoperative assessment of sentinel lymph nodes (SLNs) has the advantage of allowing breast cancer patients with tumor-positive SLNs to avoid a second surgery by immediately proceeding to axillary lymph node dissection (ALND). However, there are several reasons why the use of intraoperative assessment should be questioned. Whereas ALND was traditionally advised for all breast cancer patients with tumor-positive lymph nodes for axillary staging and locoregional control, more recent studies have demonstrated safety of omitting ALND in a substantial number of patients. In addition, there are concerns about the accuracy of intraoperative assessment methods including frozen section analysis, touch preparation cytology and one-step nucleic acid amplification. Moreover, intraoperative assessment of SLNs denies patients the opportunity to contribute to their treatment planning. In our opinion, intraoperative assessment of axillary lymph nodes should be reserved for patients who still have a strict indication for ALND. Patients with clinical node negative disease (cN0) and one or two positive SLNs can be safely treated with breast conserving surgery and radiotherapy. There has been more controversy for cN0 patients who are treated with mastectomy since radiotherapy is not routinely administered in these patients. However, there is increasing evidence that ALND may be omitted in patients undergoing mastectomy who have a low tumor-burden in their SLNs. Therefore, we defend the position that in cN0 patients undergoing mastectomy, SLNB should be performed and full pathologic evaluation of the SLN should be awaited. In cN0 patients undergoing neoadjuvant systemic therapy (NST) intraoperative assessment of SLNs can be omitted since ALND will not provide therapeutic benefit. It is being hypothesized that patients with limited axillary disease prior to NST who remain node-positive after NST could be treated safely with axillary radiotherapy instead of ALND. In these patients, omitting intraoperative assessment might be a reasonable option. In patients with extensive nodal disease prior to NST intraoperative assessment of axillary lymph nodes should be performed.

Management of the Positive Axilla in 2017

The role of surgery in breast cancer treatment and axillary staging is changing. It is not very far from today, when axillary dissection was the standard treatment and staging procedure for all stages of breast cancer. Today, we are on the edge of omitting axillary dissection even in patients with the axillary disease. In this review, we walked through the changes in axillary management throughout the past hundred years.

Axillary Nodal Management Following Neoadjuvant Chemotherapy: A Review

Importance

The increasing use of neoadjuvant chemotherapy (NAC) for operable breast cancer has raised questions about optimal local therapy for the axilla.

Observations

Sentinel lymph node biopsy (SLNB) after NAC in patients presenting with clinically negative nodes has an accuracy similar to upfront SLNB and reduces the need for axillary lymph node dissection compared with SLNB prior to NAC. In patients presenting with node-positive disease, clinical trials demonstrate that SLNB after NAC is accurate when 3 or more sentinel nodes are obtained, but long-term outcomes are lacking. The relative importance of pre- and post-NAC stage in predicting risk of locoregional recurrence remains an area of controversy.

Conclusions and Relevance

Neoadjuvant chemotherapy reduces the need for axillary lymph node dissection, and SLNB is an accurate method of determining nodal status after NAC.

Swedish prospective multicenter trial evaluating sentinel lymph node biopsy after neoadjuvant systemic therapy in clinically node-positive breast cancer

Purpose

Patients with clinically node-positive breast cancer planned for neoadjuvant systemic therapy (NAST) may draw advantages from the nodal downstaging effect and reduce the extent of axillary surgery with sentinel lymph node biopsy (SLNB) performed after NAST. Since there are concerns about lower sentinel lymph node (SLN) detection and higher false-negative rates (FNR) in this setting, our aim was to define the accuracy of SLNB after NAST.

Methods

This Swedish national multicenter trial prospectively recruited 195 breast cancer patients from ten hospitals with T1–T4d biopsy-proven node-positive disease planned for NAST between October 1, 2010 and December 31, 2015. Clinically node-negative axillary status after NAST was not mandatory. SLNB was always attempted and followed by a completion axillary lymph node dissection (ALND).

Results

The SLN identification rate was 77.9% (152/195) but improved to 80.7% (138/171) with dual mapping. The median number of SLNs was two (range 1–5). A positive SLNB was found in 52% (79/152), almost 66% (52/79) of whom had additional positive non-sentinel lymph nodes. The overall pathologic nodal response rate was 33.3% (66/195). The overall FNR was 14.1% (13/92) but decreased to 4% (2/50) when only patients with two or more sentinel nodes were analyzed.

Conclusions

In biopsy-proven node-positive breast cancer, SLNB after NAST is feasible even though the identification rate is lower than in clinically node-negative patients. Since the overall FNR is unacceptably high, the omission of ALND should only be considered if two or more SLNs are identified.

Is it time to relook the management of axilla in post-neoadjuvant breast cancer cases in a re-evolving era of current axillary management?

Aim: Axillary node dissection (AND) is an established practice, recently a conservative approach to axilla has resurged but there is reluctance to pass this benefit to neoadjuvant chemotherapy (NAC) cases, even in complete responders. Present study aims to look whether this approach is applicable to post-NAC cases. Patients & methods: Prospective study of 100 cases of NAC for breast cancer. Results: The core positive axillary nodes at diagnosis (66) after NAC had AND, 25 (38%) showed pathological complete response (pCR) in axillary nodes and 41 (62%) have residual disease. While, 34 with radiologically normal nodes, incidence of positive sentinel lymph node biopsy after NAC is lower as compared with patients without NAC. Conclusion: We conclude that it is time to re-examine axillary management in post-NAC cases with pCR, and possibly avoiding AND in 30–40% cases. Also, there is no place for upfront sentinel lymph node biopsy which offers no gain.

Is Routine Axillary Imaging Necessary in Clinically Node-Negative Patients Undergoing Neoadjuvant Chemotherapy?

BACKGROUND

The National Comprehensive Cancer Network guidelines recommend axillary imaging prior to neoadjuvant chemotherapy (NAC) in breast cancer patients who are clinically node negative (cN0) by physical examination. However, the benefit of this approach remains uncertain. The purpose of this study was to determine whether abnormal axillary imaging pre-NAC predicts nodal metastases post-NAC (ypN+) in cN0 patients.

METHODS

cN0 patients undergoing NAC followed by axillary surgery were identified. Rates of ypN+ were compared among patients with abnormal pre-treatment axillary imaging vs. normal or no pre-treatment imaging using Fisher's exact test.

RESULTS

From May 2008 to March 2016, 402 eligible cN0 patients were identified. The median age of the patients was 49.5 years, and the median tumor size was 4 cm. Of these patients, 38% were estrogen receptor-positive (ER+) and human epidermal growth factor receptor 2-negative (HER2-), 30% were HER2+ , and 32% were triple negative. All had pre-NAC mammograms, 40% axillary ultrasound, 83% MRI, and 51% PET. Abnormal nodes on imaging were seen in 208 patients (52%); 128 had pre-NAC node biopsy, and 75 were positive. Overall, 28% of the patients (n = 111) were ypN+ post-NAC. Although the incidence of ypN+ was significantly higher in patients with abnormal nodes on pre-NAC imaging (p = 0.001), 54% did not require axillary lymph node dissection (ALND) post-NAC. Among the patients with normal nodes on pre-NAC imaging, 20% were ypN+ post-NAC.

CONCLUSIONS

Half of patients with abnormal nodes on pre-NAC imaging did not require ALND post-NAC, while 20% of those with normal pre-NAC nodes had disease post-NAC, indicating that in cN0 patients already selected for NAC, axillary imaging pre-NAC does not predict the need for axillary surgery post-NAC with sufficient accuracy to be clinically useful.

Sentinel lymph node biopsy after neoadjuvant chemotherapy for breast cancer: retrospective comparative evaluation of clinically axillary lymph node positive and negative patients, including those with axillary lymph node metastases confirmed by fine needle aspiration

Background

To evaluate the accuracy of sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NAC) in breast cancer patients with axillary lymph node (ALN) metastasis.

Methods

A total of 122 patients with operable breast cancer were enrolled in this single-center retrospective study. Eighty patients were clinically diagnosed with a positive axillary lymph node (ALN) via imaging or physical examination (including 66 patients with biopsy-proven metastasis). The other 42 cases had a clinically negative ALN. After four sessions of neoadjuvant chemotherapy, patients were assigned to an ALN-positive or -negative group. The identification rate (IR) and false negative rate (FNR) were determined in the ALN-negative group.

Results

ALN changed from positive to negative after NAC in 48 patients. Among them, 46 had at least one SLN resected (total IR = 95.8 %). Eight of the 46 SLN-negative patients had pathologically confirmed metastasis of at least one non-SLN (FNR = 36 %). Fifty-five of the 56 patients with a biopsy-proven negative ALN remained ALN negative. Furthermore, 54 of the 56 patients had at least one SLN resected (IR =98.2 %). Three SLN-negative patients of the 54 had at least one positive non-SLN (FNR = 10.7 %).

Conclusions

Due to its high FNR, post-NAC SLNB is not recommended for breast cancer patients with ALN metastasis confirmed by biopsy, though their ALN may become negative after NAC. However, for operable breast cancer with negative ALN, post-NAC SLNB is feasible if the ALN remains clinically negative after NAC.

Trial registration

Retrospective evaluation.

The Feasibility and Accuracy of Sentinel Lymph Node Biopsy in Initially Clinically Node-Negative Breast Cancer after Neoadjuvant Chemotherapy: A Systematic Review and Meta-Analysis

Background

With the increased use of neoadjuvant chemotherapy (NAC) in breast cancer, the timing of sentinel lymph node biopsy (SLNB) has become increasingly important. In this study, we aimed to evaluate the feasibility and accuracy of SLNB for initially clinically node-negative breast cancer after NAC by conducting a systematic review and meta-analysis.

Methods

We searched PubMed, Embase, and the Cochrane Library from January 1, 1993 to November 30, 2015 for studies on initially clinically node-negative breast cancer patients who underwent SLNB after NAC followed by axillary lymph node dissection (ALND).

Results

A total of 1,456 patients from 16 studies were included in this review. The pooled identification rate (IR) for SLNB was 96% [95% confidence interval (CI): 95%-97%], and the false negative rate (FNR) was 6% (95% CI: 3%-8%). The pooled sensitivity, negative predictive value (NPV) and accuracy rate (AR) were 94% (95% CI: 92%-97%, I² = 27.5%), 98% (95% CI: 98%-99%, I² = 42.7%) and 99% (95% CI: 99%-100%, I² = 32.6%), respectively. In the subgroup analysis, no significant differences were found in either the IR of an SLNB when different mapping methods were used (P = 0.180) or in the FNR between studies with and without immunohistochemistry (IHC) staining (P = 0.241).

Conclusion

Based on current evidence, SLNB is technically feasible and accurate enough for axillary staging in initially clinically node-negative breast cancer patients after NAC.

A mini-review on factors and countermeasures associated with false-negative sentinel lymph node biopsies in breast cancer

Sentinel lymph node biopsy (SLNB) is a new surgical technique for local axillary lymph nodes (ALNs) of breast cancer. Large-scale clinical trials have confirmed that undergoing SLNB and ALN dissection (ALND) showed no significant difference for sentinel lymph node (SLN)-negative patients in terms of disease-free survival, overall survival and recurrence-free survival. However, false-negative results are still the main concern of physicians as well as patients who undergo SLNB instead of ALND. The American Society of Breast Surgeons established a task force to suggest acceptable standards for SLNB. In 2000, the task force recommended that the identification rate for SLNB be 85% or higher and the false-negative rate be 5% or lower. This review focuses on clinical factors (tumor volume, multifocal/multi-center cancers, neoadjuvant chemotherapy and skip metastasis), tracer techniques and pathological factors affecting SLNB and explores methods for reducing the false-negative rate.