Breast-conserving surgery is not associated with increased local recurrence in patients with early-stage node-negative triple-negative breast cancer treated with neoadjuvant chemotherapy

BACKGROUND

Neoadjuvant chemotherapy (NACT) is routinely used for patients with triple-negative breast cancer (TNBC). Upfront breast-conserving therapy (BCT) consisting of breast-conserving surgery (BCS) and adjuvant radiotherapy (RT) has been shown to be associated with improved outcome in patients with early TNBC as compared to mastectomy.

METHODS

We identified 2632 patients with early TNBC from the German Breast Group meta-database. Patients with cT1-2 cN0 and ypN0, available surgery and follow-up data were enrolled. Data of 1074 patients from 8 prospective NACT trials were available. Endpoints of interest were locoregional recurrence as first site of relapse (LRR), disease-free survival (DFS) and overall survival (OS). We performed univariate and multivariate Fine-Gray analysis and Cox regression models.

RESULTS

After a median follow-up of 64 months, there were 94 (8.8%) locoregional events as first site of relapse. Absence of pathologic complete response (pCR) was associated with increased LRR upon uni- and multivariate analysis (hazard ratio [HR] = 2.28; p < 0.001 and HR = 2.22; p = 0.001). Type of surgery was not associated with LRR. Patients in the BCS-group had better DFS and OS (DFS: HR = 0.47; p < 0.001 and OS: HR = 0.40; p < 0.001). BCS was associated with improved DFS and OS upon multivariate analysis (DFS: HR = 0.51; p < 0.001; and OS HR = 0.43; p < 0.001), whereas absence of pCR was associated with worse DFS and OS (DFS: HR = 2.43; p < 0.001; and OS: HR = 3.15; p < 0.001).

CONCLUSIONS

In this retrospective analysis of patients with early stage node-negative TNBC treated with NACT, BCS was not associated with an increased risk of LRR but with superior DFS and OS.

Is contrast-enhanced mammography (CEM) an alternative to MRI in assessing the response to primary systemic therapy of breast cancer?

PURPOSE

To evaluate the accuracy of contrast-enhanced mammography (CEM) and magnetic resonance imaging (MRI) in the assessing radiological response to primary systemic therapy (PST).

METHOD

Prospective study between February 2021 and October 2022. Women with breast cancer and indication of PST were enrolled. CEM and MRI were performed before and after PST, and the findings, including size and radiological response pattern, were compared with the size of the residual lesion measured in surgical specimens and its Miller-Payne classification (considered the gold standard). Two of four independent radiologists, with 2 years of CEM experience and 10 years of MRI experience, reviewed the images while being blinded to the results of the other technique. The agreement between measurements was evaluated using the Pearson correlation coefficient (r) and Lin's coefficient.

RESULTS

Forty-eight women with breast cancer who required PST were enrolled in the study, with a mean age of 57.21 ± 10.14 years. A total of thirty-three participants (68.75 %) completed the study. The correlation between CEM and MRI measurements was high before PST (r: 0.97), and local staging was identical for 45 out of 48 patients. MRI demonstrated better accuracy in predicting residual tumor size than CEM, with Lin's coefficient 0.91 and 0.73, respectively. However, no significant differences were observed in predicting response to therapy. Both methods tended to overestimate the size and degree of response in our study, with mean overestimations of 2.87 mm in CEM and 0.51 mm in MRI.

CONCLUSION

CEM was found to be as accurate as MRI in predicting response to PST, indicating its potential as an alternative imaging technique, but further research is necessary.

Benefit of postoperative regional nodal irradiation in patients receiving preoperative systemic therapy with docetaxel/carboplatin/trastuzumab/pertuzumab for HER2-positive breast cancer

AIM

The role of regional nodal irradiation (RNI) after preoperative systemic treatment (PST) with targeted therapy for HER2-positive breast cancer remains uncertain. This study aimed to investigate the impact of RNI on locoregional recurrence (LRR) and disease-free survival (DFS) outcomes after docetaxel/carboplatin/trastuzumab/pertuzumab (TCHP) for PST.

METHODS

We retrospectively analyzed 255 patients who were treated with six cycles of TCHP between 2016 and 2019. The patients were divided into four groups based on clinical nodal involvement: group A, with no nodal disease; group B, with axillary lymph node (AXL) level I; group C, with AXL level I with II/III; and group D, with supraclavicular or internal mammary nodes.

RESULTS

The RNI group had more advanced nodal disease (C/D) than the no RNI group (56.9 % vs. 6.8 %). With a median follow-up of 51.3 months, there were two (0.8 %), three (1.2 %), and 15 (5.9 %) local, regional, and distant metastases, respectively. LRR did not differ significantly according to the RNI (2.6 % vs. 1.0 %, p = 0.651). Group D had the most frequent distant metastases (17.5 %; p = 0.005). The 4-year DFS rate was 92.7 %, and DFS did not improve significantly after RNI (p = 0.074). When stratified by clinical nodal groups and pathological axillary response, RNI had no effect on LRR/DFS outcomes.

CONCLUSION

With a rare incidence of LRR, RNI did not significantly affect LRR or DFS in patients with HER2-positive breast cancer after with PST-TCHP. However, intensive systemic treatment is required for advanced diseases (C/D). Selective de-intensified RNI and intensified systemic treatment should be investigated in future studies.

Nodal response to primary systemic therapy predicts prognosis of cN3c breast cancer patients receiving multimodality therapy

AIM

To investigate the survival outcomes, patterns and risks of recurrence in cN3c breast cancer patients after multimodality therapy, as well as the predictors of candidates for ipsilateral supraclavicular (SCV) area boosting.

METHOD

Consecutive cN3c breast cancer patients from January 2009 to December 2020 were retrospectively reviewed. Based on nodal response to primary systemic therapy (PST), patients were categorized into three groups: clinical complete response (cCR) not achieved in SCV lymph nodal (SCLN, Group A), SCLN cCR but axillary node (ALN) did not achieve pathological complete response (pCR, Group B), cCR in SCLN and pCR in ALN (Group C).

RESULTS

The median follow-up time was 32.7 months. The 5-year overall survival (OS) and recurrence-free survival (RFS) were 64.6% and 43.7% respectively. Multivariate analysis showed cumulative SCV dose and ypT stage, ALN response and SCV response to PST were significantly associated with OS and RFS respectively. Compared with Group A or B, Group C showed significantly improved 3 y-RFS (53.8% vs 73.6% vs 100%, p = 0.003), and the lowest rate of DM as first failure (37.9% vs 23.5% vs 0%, p = 0.010). In Group A, the 3 y-OS for patients receiving the cumulative SCV dose of ≥60 Gy versus <60 Gy was 78.0% versus 57.3% (p = 0.029).

CONCLUSION

Nodal response to PST is an independent prognostic factor for survival and pattern of failure. A cumulative SCV dose of ≥60 Gy is positively associated with improved OS, especially in Group A. Our data supports the perspective of optimizing radiotherapeutic strategy based on nodal response.

De-escalation of axillary irradiation for early breast cancer - Has the time come?

Introduction of sentinel lymph node biopsy, initially in clinically node-negative and subsequently in patients presenting with involved axilla and downstaged by primary systemic therapy, allowed for significant decrease in morbidity compared to axillary lymph node dissection. Concurrently, regional nodal irradiation was demonstrated to improve outcomes in most node-positive patients. Additionally, over the last decades, introduction of more effective systemic therapies has resulted in improvements not only at distant sites, but also in locoregional control, creating space for de-escalation of locoregional treatments. We discuss the data on de-escalation in axillary surgery and irradiation, both in patients undergoing upfront surgery and primary systemic therapy, with special emphasis on the feasibility of omission of nodal irradiation in patients undergoing primary systemic therapy. In view of the accumulating evidence, omission of axillary irradiation may be considered in clinically node-positive patients converting after primary systemic therapy to pathologically negative nodes on sentinel lymph node biopsy (preferably also with in-breast pCR), presenting with lower initial nodal stage, older age and were treated with breast-conserving surgery followed by whole breast irradiation. Omission of regional nodal irradiation in patients with aggressive tumor phenotypes achieving a pCR is under investigation. In patients undergoing preoperative endocrine therapy the adoption of axillary management strategies utilized in case of upfront surgery seems more suitable than those used in post chemotherapy-based primary systemic therapy setting.

Prognostic and Clinicopathological Correlations of Cell Cycle Marker Expressions before and after the Primary Systemic Therapy of Breast Cancer

We aimed to analyze the expression of cell-cycle regulation markers - minichromosome maintenance protein 2 (MCM2), Ki-67, Cyclin-A and phosphohistone-H3 (PHH3) - in pre-treatment core-biopsy samples of breast carcinomas in correlation with known predictive and prognostic factors. Totally 52 core biopsy samples obtained prior to neoadjuvant therapy were analyzed. Immunohistochemistry was performed to analyze the expression of MCM2, Ki-67, Cyclin A and PHH3, which were correlated with the following clinicopathological parameters: clinical TNM, tumor grade, biological subtype, the presence of tumor infiltrating lymphocytes (TIL), pathological tumor response rate to the neoadjuvant therapy and patient survival. All investigated markers showed higher expression in high grade and in triple negative tumors (p < 0.01 and p < 0.05, respectively). Hormone receptor negative tumors showed significantly higher expression of Ki-67 (p < 0.01), MCM2 (p < 0.01) and Cyclin A (p < 0.01) than hormone receptor positive ones. Tumors with increased TIL showed significantly higher Ki-67 expression (p = 0.04). Pattern analysis suggested that novel cell-cycle marker-based subgrouping reveals predictive and prognostic potential. Tumors with high MCM2, Cyclin A or PHH3 expression showed significantly higher rate of pathological complete remission. Tumors with early relapse (progression-free survival ≤2 years) and shortened overall survival also show a higher rate of proliferation. Our cell cycle marker (Ki-67, MCM2, Cyclin A, PHH3) based testing could identify tumors with worse prognosis, but with a favorable response to primary systemic therapy. The pattern of cell-cycle activity could also be useful for predicting early relapse, but our findings need to be further substantiated in larger patient cohorts.

Sentinel node biopsy after primary systemic therapy in node positive breast cancer patients: Time trend, imaging staging power and nodal downstaging according to molecular subtype

BACKGROUND

The management of axilla after Primary Systemic Therapy (PST) for breast cancer is a highly debated field. Despite the proven axillary downstaging occurring after PST, there is still some degree of reluctance in applying sentinel node biopsy (SNB) in the neoadjuvant setting.

PATIENTS AND METHODS

We performed a retrospective analysis on 181 PST patients with axillary positive nodes at presentation treated between 2005 and 2017 at San Raffaele Hospital in Milan. The aim was to observe the application time trend of SNB, to determine the imaging staging power and the axillary downstaging according to molecular subtypes.

RESULTS

Median follow-up after surgery was 32.5(IQR: 12-59) months. After PST, 119 (65.7%) patients had no clinically palpable nodes, 72 (39.7%) converted to N0 on final imaging and 34 (18.8%) underwent SNB with an increasing application trend. Axillary-US showed the highest accuracy (69.3%) in re-staging axilla after PST. Staging power of preoperative testing varied with tumour biology: Positive Predictive Value was higher in Luminal A (80% for clinical examination and 100% for axillary-US) and Luminal B (72% and 70.5%) tumours, whilst Negative Predictive Value was higher in HER2 positive (100% and 93.3%), and triple negative (71.4% and 93.3%) tumours. Ninety five (52.5%) patients experienced axillary downstaging after PST, by molecular subtype 15% (3/20) in Luminal A, 46.4% (45/97) in Luminal B, 90.9% (20/22) in HER2+ and 70.3% (26/37) in triple negative breast tumours.

CONCLUSION

SNB application after PST for breast cancer in node positive patients at presentation is increasing. Pre-operative axillary imaging and tumour biology help identify patients who might be candidates for SNB as a single staging procedure.

ypN+) in patients with breast cancer converting from cN+ to ycN0 through primary systemic therapy (PST)

Optimization of axillary staging among patients converting from clinically node-positive disease to clinically node-negative disease through primary systemic therapy is needed. We aimed at developing a nomogram predicting the probability of positive axillary status after chemotherapy based on clinical/pathological parameters. Patients from study arm C of the SENTINA trial were included. Univariable/multivariable analyses were performed for 13 clinical/pathological parameters to predict a positive pathological axillary status after chemotherapy using logistic regression models. Odds ratios and 95%-confidence-intervals were reported. Model performance was assessed by leave-one-out cross-validation. Calculations were performed using the SAS Software (Version 9.4, SAS Institute Inc., Cary, NC, USA). 369 of 553 patients in Arm C were included in multivariable analysis. Stepwise backward variable selection based on a multivariable analysis resulted in a model including estrogen receptor (ER) status (odds ratio (OR) 3.916, 95% confidence interval (CI) 2.318-6.615, p < 0.001), multifocality (OR 2.106, 95% CI 1.203-3.689, p = 0.0092), lymphovascular invasion (OR 9.196, 95% CI 4.734-17.864, p < 0.001), and sonographic tumor diameter after PST (OR 1.034, 95% CI 1.010-1.059, p = 0.0051). When validated, our model demonstrated an accuracy of 70.2% using 0.5 as cut-point. An area under the curve of 0.81 was calculated. The use of individual parameters as predictors of lymph node status after chemotherapy resulted in an inferior accuracy. Our model was able to predict the probability of a positive axillary nodal status with a high accuracy. The use of individual parameters showed reduced predictive performance. Overall, tumor biology was the strongest parameter in our models.

Sentinel lymph node surgery after neoadjuvant chemotherapy in patients with T2 to T4, N0 and N1 breast cancer

BACKGROUND

Histological status of axillary lymph nodes is an important prognostic factor in patients receiving surgery for breast cancer (BC). Sentinel lymph node (SLN) biopsy (B) has rapidly replaced axillary lymph node dissection (ALND), and is now the standard of care for axillary staging in patients with clinically node-negative (N0) operable BC. The aim of this study is to compare pretreatment lymphoscintigraphy with a post primary systemic treatment (PST) scan in order to reduce the false-negative rates for SLNB.

METHODS

In this single-institution study we considered 170 consecutive T2-4 N0-1 M0 BC patients treated with anthracycline-based PST. At the time of incisional biopsy, we performed sentinel lymphatic mapping. After PST, all patients repeated lymphoscintigraphy with the same methodology. During definitive surgery we performed further sentinel lymphatic mapping, SLNB and ALND.

RESULTS

The SLN was removed in 158/170 patients giving an identification rate of 92.9% (95% confidence interval (CI) = 88.0-96.3%) and a false-negative rate of 14.0% (95% CI = 6.3-25.8%). SLNB revealed a sensitivity of 86.0% (95% CI = 74.2-93.7%), an accuracy of 94.9% (95% CI = 90.3-97.8%) and a negative predictive value of 92.7% (95% CI = 86.1-96.8%).

CONCLUSION

Identification rate, sensitivity and accuracy are in accordance with other studies on SLNB after PST, even after clinically negative node conversion following PST. This study confirms that diagnostic biopsy and neoadjuvant chemotherapy maintain breast lymphatic drainage unaltered.

Expression of cell cycle markers is predictive of the response to primary systemic therapy of locally advanced breast cancer

We aimed to analyze to what extent expression of four cell cycle regulation markers-minichromosome maintenance protein (MCM2), Ki-67, cyclin A, and phosphohistone-H3 (PHH3)-predict response to primary systemic therapy in terms of pathological complete remission (pCR). In search of an accurate and reproducible scoring method, we compared computer-assisted (CA) and routine visual assessment (VA) of immunoreactivity. We included 57 patients with breast cancer in the study. The cell cycle markers were detected using immunohistochemistry on pre-therapy core biopsy samples. Parallel CA (validated by manual labeling) and standard VA were performed and compared for diagnostic agreement and predictive value for pCR. CA and VA results were dichotomized based on receiver operating characteristic analysis defined optimal cut-off values. "High" was defined by staining scores above the optimal cut-off, while "low" had staining scores below the optimal cut-off. The CA method resulted in significantly lower values for Ki-67 and MCM2 compared to VA (mean difference, -3.939 and -4.323). Diagnostic agreement was highest for cyclin A and PHH3 (-0.586 and -0.666, respectively). Regardless of the method (CA/VA) used, all tested markers were predictive of pCR. Optimal cut-off-based dichotomization improved diagnostic agreement between the CA and VA methods for every marker, in particular for MCM2 (κ = 1, p < 0.000). Cyclin A displayed excellent agreement (κ = 0.925; p < 0.000), while Ki-67 and PHH3 showed good agreement (κ = 0.789, p < 0.000 and κ = 0.794, p < 0.000, respectively). We found all cell cycle markers (Ki-67, MCM2, cyclin A, and PHH3) predictive of pCR. Diagnostic agreement between CA and VA was better at lower staining scores but improved after optimal cut-off-based dichotomization.

Predictive and prognostic value of FDG-PET/CT imaging and different response evaluation criteria after primary systemic therapy of breast cancer

OBJECTIVES

(1) To predict pathological complete remission (pCR) and survival after primary systemic therapy (PST) in patients diagnosed with breast cancer by using two different PET/CT based scores: a simplified PERCIST-based PET/CT score (Method 1) and a combined PET/CT score supplemented with the morphological results of the RECIST system (Method 2) and (2) to assess the effect of different breast carcinoma subtypes on tumor response and its evaluation.

METHODS

Eighty-eight patients were enrolled in the study who underwent PET/CT imaging before and after PST. PET/CTs were evaluated by changes in maximum Standardized Uptake Value (SUVmax) and tumor size. Method 1 and 2 were applied to predict pathological complete remission (pCR). Kaplan-Meier analyses for survival were performed. Classification into biological subtypes was performed based on the pre-therapeutic tumor characteristics.

RESULTS

A total of 30/88 patients showed pCR (34.1 %). Comparing pCR/non-pCR patient groups, significant differences were detected by changes in SUVmax (p < 0.001) and tumor size (p < 0.001) regarding the primary breast lesions. To predict pCR, Method 2 had higher sensitivity (72.4 % vs. 44.8 %) and negative predictive value (57.9 % vs. 45.8 %) with lower false negativity rate (16 vs. 32) than Method 1. pCR rate was higher in Her2-positive and triple negative tumors. Despite the significant differences detected between the biological subtypes regarding changes in primary tumor SUVmax (p = 0.007) and size (p = 0.015), the subtypes only had significant impact on response evaluation with Method 2 and not with Method 1. In our study, neither clinical nor pathological CR were predictors of longer progression-free survival.

CONCLUSIONS

Our results suggest that combined PET/CT criteria are more predictive of pCR. The effect of biological subtypes is significant on pCR rate as well as on the changes in FDG-uptake and morphological tumor response. Response evaluation with combined criteria was also able to reflect the differences between the biological behavior of breast tumor subtypes.

Exploring patient experiences of neo-adjuvant chemotherapy for breast cancer

BACKGROUND AND PURPOSE

Neo-adjuvant chemotherapy is recommended for 'inoperable' locally advanced and inflammatory breast cancers. For operable breast cancers, trials indicate no survival differences between chemotherapy given pre or post-surgery. Communicating evidence based information to patients is complex and studies examining patient experiences of neo-adjuvant chemotherapy are lacking. This study aims to explore the experiences of women who received neo-adjuvant chemotherapy for breast cancer.

METHODS

A qualitative approach using in-depth interviews with 20 women who had completed neo-adjuvant chemotherapy for breast cancer. Interview data were analysed using thematic analysis.

RESULTS

The sample included a relatively young group of women, with caring responsibilities. Five main themes emerged: coping with the rapid transition from 'well' to 'ill', information needs and decision making, needing support and empathy, impact on family, and creating a new 'normal'. More support was needed towards the end of chemotherapy, when side effects were at their most toxic, and decisions about forthcoming surgery were being made. Some women were referred to psychological services, but usually when a crisis point had been reached.

CONCLUSION

Information and support would have been beneficial at key time points. This information is vital in developing services and interventions to meet the complex needs of these patients and potentially prevent late referral to psychological services. Specialist oncology nurses are able to develop empathetic relationships with patients and have the experience, knowledge and skills to inform and support women experiencing neo-adjuvant chemotherapy. Targeting key time points and maintaining relationship throughout neo-adjuvant chemotherapy would be highly beneficial.

Primary systemic therapy for breast cancer: Does the patient's involvement in decision-making create a new future?

OBJECTIVE

Primary systemic therapy (PST) followed by surgery is the standard initial treatment for locally advanced breast cancer (LABC). However, some patients are averse to mastectomy or breast-conserving surgery and do not consent to these procedures. The reasons for this controversial decision, the factors influencing the decision-making and optimal solutions for decision aiding need to be investigated.

METHODS

We addressed these questions by a review of literature on the possibilities associated with different patient choices and subsequent treatment options in relation to LABC.

RESULTS

A total of 5 reviews and 22 clinical studies were summarized in relation to decision making and the most successful decision aids. A discussion is given of the issues of those few patients who cannot be convinced to undergo surgery.

CONCLUSION

Currently there is no guideline for the treatment of patients who reject the surgical procedures after PST. Medical oncologists should be able to apply decision aid modalities in a personalized manner to give all needed information to their patients thereby ensuring a deliberate decision-making process, facilitating acceptance of a need for surgery, and thus improving the chances of prolonged survival.

PRACTICE IMPLICATIONS

Currently multidisciplinary tumor boards are the most suitable decision aids in oncological practice.

Detection of disseminated tumor cells in locally advanced breast cancer patients before primary systemic therapy

AIM

To assess the prevalence and prognostic power of disseminated tumor cells (DTC) in patients with locally advanced breast cancer (LABC) before primary systemic therapy (PST).

MATERIALS AND METHODS

LABC patients attending our Breast Unit were studied between 2002 and 2012, all of them being considered for PST. To determine the presence of DTC, posterior iliac crest aspirates were obtained and marrow samples were processed by gradient separation with Ficoll (Lymphoprep(®)) and immunohistochemical staining using the antiCK A45-B/B3 (EPIMET) antibody. Clinicopathologic variables were recorded before and after PST to assess response. Disease-free survival (DFS) and overall survival (OS) were determined after follow-up. The presence of DTC as a predictor of response to PST and as a prognostic tool for OS and DSF was evaluated.

RESULTS

DTC were observed in 26% of 47 patients included in the study. PST consisted of chemotherapy in 94% and hormone therapy in 6%. Breast-conserving therapy was attained in 33%. Mean follow-up was 68 months. Complete clinical response (CR) after PST was seen in 26%, disease recurrence in 38%, and cancer-related death in 8%; tumor size and negative estrogen receptors were significant predictors of CR and mastectomy was associated with DFS. Persistent axillary disease after PST and previous recurrence were predictive of OS. DTC were detected more often in patients who did not achieve CR and those who presented recurrence. DTC detection was a significant prognostic factor for a worse OS (OR = 7.62; CI95%: 1.46-39.61; p = 0.009) and a decreased survival time (62 versus 82 months, p = 0.004).

CONCLUSION

Presence of DTC before PST was found in a significant number of patients with LABC. DTC were found to be a significant prognostic factor for cancer-related death. DTC could be a surrogate predictor of response to PST and also of disease recurrence in LABC patients.

Past, present and future of primary systemic treatment in breast cancer

Primary systemic treatment is a fundamental part of breast cancer therapy, and it is applied to non-surgical and locally advanced tumours as well as surgical tumours to increase the likelihood of conservative treatment. Its aim is to achieve the best possible survival with better cosmetic results and with the lowest number of treatment-related secondary effects. Before treatment is started, it is necessary to attain the best knowledge of the biological features and locoregional extension of the tumour. To do so, it is necessary to obtain a biopsy of the lesion with a wide bore needle, as well as good radiological knowledge of the disease. Therefore, currently, the use of a dynamic magnetic resonance imaging (MRI) of the breast should be included in all cases. In addition, before it is started, especially in those tumours in which conservative treatment is considered, one or several radiopaque markers should be put into place to make it possible to locate the area to be treated if there is a considerable or complete response. Systemic treatment is mainly based on combined chemotherapy with anthracyclins and taxanes, in addition to some biological agents with demonstrated efficiency for increasing the likelihood of complete disease response (trastuzumab in patients with Her-2/neu overexpression). However, there is room for neoadjuvant hormone treatment, in patients with hormone receptor overexpression, especially in those cases in which chemotherapy is contraindicated as well as in elderly patients with a relatively short life expectancy. The assessment of preoperative treatment should be based on adequate radiological tests, and nowad these should include MRI before taking decisions about adequate surgical treatment. The objective of primary treatment is to be able to increase survival and improve the chances of local treatment in the case of locally advanced treatment, achieving results that are at least equal to those of adjuvant treatment in the case of surgical tumours, but with greater chances of conservative surgery. Although the objective is survival, achieving complete pathological response seems to be a reasonable related objective, although these are more closely linked in some tumour subtypes.

Feasibility of sentinel lymph node biopsy in breast cancer patients with initial axillary lymph node metastasis after primary systemic therapy

Purpose

Primary systemic therapy (PST) downstages up to 40% of initial documented axillary lymph node (ALN) metastases in breast cancer. The current surgical treatment after PST consists of breast tumor resection and axillary lymph node dissection (ALND). This strategy, however, does not eliminate unnecessary ALND in patients with complete remission of axillary metastases. The aim of this study was to examine the accuracy of sentinel lymph node biopsy (SLNB) after PST among patients with documented ALN metastasis at presentation and to identify the rate of pathologic complete-remission (CR) with ALN after PST.

Methods

We analyzed 66 patients with ALN metastasis that was pathologically proven preoperatively who underwent SLNB and concomitant ALND after PST. Axillary ultrasound (AUS) was used to evaluate the clinical response of initially documented ALN metastasis after PST. Intraoperative lymphatic mapping was performed using blue dye with or without radioisotope.

Results

After PST, 34.8% of patients had clinical CR of ALN on AUS and 28.8% patients had pathologic CR of ALN. The overall success rate of SLNB after PST was 87.9%, and the sentinel lymph node identification rate in patients with clinical CR was 95.7%. In patients with successful lymphatic mapping, 70.7% of patients had residual axillary metastases. The overall accuracy and false-negative rate were 87.9% and 17.1% in all patients: 95.5% and 10.0% in patients with clinical CR of ALN, and 83.3% and 19.4% in patients with residual axillary disease after PST.

Conclusion

Our findings suggest that SLNB may be feasible in patients with initial documented ALN metastasis who have clinical CR for metastatic ALN after PST. Further investigation in a prospective setting should be performed to confirm our results.