Trends on Axillary Surgery in Nondistant Metastatic Breast Cancer Patients Treated Between 2011 and 2015: A Dutch Population-based Study in the ACOSOG-Z0011 and AMAROS Era

Personalizing Locoregional Therapy in Patients With Breast Cancer in 2024: Tailoring Axillary Surgery, Escalating Lymphatic Surgery, and Implementing Evidence-Based Hypofractionated Radiotherapy

The management of axillary lymph nodes in breast cancer is continually evolving. Recent data now support omitting axillary lymph node dissection (ALND) in most patients with metastases in up to two sentinel lymph nodes (SLNs) during upfront surgery and those with residual isolated tumor cells after neoadjuvant chemotherapy (NACT). In the upfront surgery setting, ALND is still indicated, however, in patients with clinically node-positive breast cancer or more than two positive SLNs and, after NACT, in case of residual micrometastases and macrometastases. Omission of the sentinel lymph node biopsy (SLNB) can be considered in many postmenopausal patients with small luminal breast cancer, particularly when axillary ultrasound is negative. Several randomized controlled trials (RCTs) are currently aiming at eliminating the remaining indications for ALND and also establishing omission of SLNB in a broader patient population. The movement to deescalate axillary staging is in part because of the association between ALND and lymphedema, which is swelling of an extremity because of lymphatic damage and obstructed lymphatic drainage. To reduce the risk of developing this condition, patients undergoing ALND can undergo reverse mapping of the axilla and immediate reconstruction or bypass of the lymphatics from the involved extremity. Decongestion and compression are the foundation of conservative treatment for established lymphedema, while lymphovenous bypass and lymph node transfer are surgical procedures to address the physiologic dysfunction. Radiotherapy is an essential component of breast locoregional therapy: more than three decades of radiation research has optimized treatment according to patient's risk of local recurrence while substantially reducing the number of treatment visits. High-quality RCTs have shown the efficacy and safety of hypofractionation-more than 2Gy radiation dose per treatment (fraction)-significantly reducing the burden of radiotherapy treatment for many patients with breast cancer. In 2024, guidelines recommend no more than 15-16 fractions for whole-breast and nodal radiotherapy, with some recommending five fractions for whole-breast radiotherapy. In addition, simultaneous integrated boost (SIB) has been shown to be noninferior to sequential boost with regards to ipsilateral breast tumor recurrence with similar or reduced long-term side effects, also reducing overall treatment length. Further RCTs are underway investigating other indications for five fractions, including SIB and regional node irradiation, such that, in future, it may be possible for the majority of breast radiotherapy patients to be treated with a 1-week course. This manuscript serves to outline the latest updates on axillary surgical staging, lymphatic surgery, and evidence-based radiotherapy in the treatment of breast cancer.

Characteristics and risk factors of axillary lymph node metastasis of microinvasive breast cancer

PURPOSE

To select patients who would benefit most from sentinel lymph node biopsy (SLNB) by investigating the characteristics and risk factors of axillary lymph node metastasis (ALNM) in microinvasive breast cancer (MIBC).

METHODS

This retrospective study included 1688 patients with MIBC who underwent breast surgery with axillary staging at the Asan Medical Center from 1995 to 2020.

RESULTS

Most patients underwent SLNB alone (83.5%). Seventy (4.1%) patients were node-positive, and the majority had positive lymph nodes < 10 mm, with micro-metastases occurring frequently (n = 37; 55%). Node-positive patients underwent total mastectomy and axillary lymph node dissection (ALND) more than breast-conserving surgery (BCS) and SLNB compared with node-negative patients (p < 0.001). In the multivariate analysis, independent predictors of ALNM included young age [odds ratio (OR) 0.959; 95% confidence interval (CI) 0.927-0.993; p = 0.019], ALND (OR 11.486; 95% CI 5.767-22.877; p < 0.001), number of lymph nodes harvested (≥ 5) (OR 3.184; 95% CI 1.555-6.522; p < 0.001), lymphovascular invasion (OR 6.831; 95% CI 2.386-19.557; p < 0.001), presence of multiple microinvasion foci (OR 2.771; 95% CI 1.329-5.779; p = 0.007), prominent lymph nodes in preoperative imaging (OR 2.675; 95% CI 1.362-5.253; p = 0.004), and hormone receptor positivity (OR 2.491; 95% CI 1.230-5.046; p = 0.011).

CONCLUSION

Low ALNM rate (4.1%) suggests that routine SLNB for patients with MIBC is unnecessary but can be valuable for patients with specific risk factors. Ongoing trials for omitting SLNB in early breast cancer, and further subanalyses focusing on rare populations with MIBC are necessary.

Axillary Surgery for Breast Cancer in 2024

Axillary surgery for patients with breast cancer (BC) in 2024 is becoming increasingly specific, moving away from the previous 'one size fits all' radical approach. The goal is to spare morbidity whilst maintaining oncologic safety. In the upfront surgery setting, a first landmark randomized controlled trial (RCT) on the omission of any surgical axillary staging in patients with unremarkable clinical examination and axillary ultrasound showed non-inferiority to sentinel lymph node (SLN) biopsy (SLNB). The study population consisted of 87.8% postmenopausal patients with estrogen receptor-positive, human epidermal growth factor receptor 2-negative BC. Patients with clinically node-negative breast cancer and up to two positive SLNs can safely be spared axillary dissection (ALND) even in the context of mastectomy or extranodal extension. In patients enrolled in the TAXIS trial, adjuvant systemic treatment was shown to be similar with or without ALND despite the loss of staging information. After neoadjuvant chemotherapy (NACT), targeted lymph node removal with or without SLNB showed a lower false-negative rate to determine nodal pathological complete response (pCR) compared to SLNB alone. However, oncologic outcomes do not appear to differ in patients with nodal pCR determined by either one of the two concepts, according to a recently published global, retrospective, real-world study. Real-world studies generally have a lower level of evidence than RCTs, but they are feasible quickly and with a large sample size. Another global real-world study provides evidence that even patients with residual isolated tumor cells can be safely spared from ALND. In general, few indications for ALND remain. Three randomized controlled trials are ongoing for patients with clinically node-positive BC in the upfront surgery setting and residual disease after NACT. Pending the results of these trials, ALND remains indicated in these patients.

The Impact of Sentinel Lymph Node Biopsy on Female Patients With T3-4c Breast Cancer and 1-2 Positive Lymph Nodes: A Population-Based Cohort Study

PURPOSE

This study aimed to evaluate the efficacy of sentinel lymph node biopsy (SLNB) in patients diagnosed with cT3-4c breast cancer with no more than 2 positive sentinel lymph nodes.

METHODS

Using data from the Surveillance, Epidemiology, and End Results (SEER) database, this retrospective study identified patients diagnosed with T3-4c breast cancer between 2010 and 2015. These patients were then categorized into 2 groups: the SLNB group, which underwent examination of 1-5 regional lymph nodes and the axillary lymph node dissection (ALND) group, which underwent examination of ≥10 regional lymph nodes. Propensity score matching analysis was used to assess the efficacy of SLNB in cT3-4c patients.

RESULTS

A total of 1139 patients were included in the analysis, with 423 and 716 patients in the SLNB and ALND groups, respectively. The 10-year overall survival (OS) and breast cancer-specific survival (BCSS) rates in the SLNB group were 66.1% and 76.3%, respectively, compared with 66.0% and 73.8%, respectively. Statistical analysis revealed no significant differences between the 2 groups in terms of OS (HR = 1.00, 95% CI = 0.80-1.25, P = .997) and BCSS (HR = 1.08, 95% CI = 0.83-1.41, P = .551). Even after 1:1 propensity score matching, there were no significant differences in OS (HR = 0.87, 95% CI = 0.65-1.16, P = .341) and BCSS (HR = 0.82, 95% CI = 0.59-1.16, P = .266) between the 2 groups.

CONCLUSION

This study demonstrates that SLNB does not adversely affect the survival of cT3-4c breast cancer patients with 1-2 sentinel lymph node metastases.

Trends of Axillary Treatment in Sentinel Node-Positive Breast Cancer Patients Undergoing Mastectomy

BACKGROUND

The ACOSOG-Z0011- and the AMAROS-trial obviated the need for axillary surgery in most sentinel node-positive (SLN+) breast cancer patients undergoing breast-conserving surgery (BCS). Data for patients who undergo mastectomy is scarce. The purpose of this study was to investigate patterns of axillary treatment in SLN+ patients treated by mastectomy in the years after the publication of landmark studies regarding axillary treatment in SLN+ breast cancer patients undergoing BCS.

METHODS

This was a population-based study in cT1-3N0M0 breast cancer patients treated by mastectomy and staged as SLN+ between 2009 and 2018. The performance of an axillary lymph node dissection (ALND) and/or administration of postmastectomy radiotherapy (PMRT) were primary outcomes and were studied over time.

RESULTS

The study included 10,633 patients. The frequency of ALND performance decreased from 78% in 2009 to 10% in 2018, whereas PMRT increased from 4 to 49% (P < 0.001). In ≥N1a patients, ALND performance decreased from 93 to 20%, whereas PMRT increased to 70% (P < 0.001). In N1mi and N0itc patients, ALND was abandoned during the study period, whereas PMRT increased to 38% and 13% respectively (P < 0.001), respectively. Age, tumor subtype, N-stage, and hospital type affected the likelihood that patients underwent ALND.

CONCLUSIONS

In this study in SLN+ breast cancer patients undergoing mastectomy, use of ALND decreased drastically over time. By the end of 2018 most ≥N1a patients received PMRT as the only adjuvant axillary treatment, whereas the majority of N1mi and N0itc patients received no additional treatment.

De-implementation of Axillary Dissection in Women Undergoing Mastectomy for Breast Cancer

BACKGROUND

Completion axillary lymph node dissection (cALND) was standard treatment for breast cancer with positive sentinel lymph nodes (SLNs) until 2011, when data from the Z11 and AMAROS trials challenged its survival benefit in early stage breast cancer. We assessed the contribution of patient, tumor, and facility factors on cALND use in patients undergoing mastectomy and SLN biopsy.

PATIENTS AND METHODS

Using the National Cancer Database, patients diagnosed from 2012 to 2017 who underwent upfront mastectomy and SLN biopsy with at least one positive SLN were included. A multivariable mixed effects logistic regression model was used to determine the effect of patient, tumor, and facility variables on cALND use. Reference effect measures (REM) were used to compare the contribution of general contextual effects (GCE) to variation in cALND use.

RESULTS

From 2012 to 2017, the overall use of cALND decreased from 81.3% to 68.0%. Overall, younger patients, larger tumors, higher grade tumors, and tumors with lymphovascular invasion were more likely to undergo cALND. Facility variables, including higher surgical volume and facility location in the Midwest, were associated with increased use of cALND. However, REM results showed that the contribution of GCE to the variation in cALND use exceeded that of the measured patient, tumor, facility, and time variables.

CONCLUSIONS

There was a decrease in cALND use during the study period. However, cALND was frequently performed in women after mastectomy found to have a positive SLN. There is high variability in cALND use, mainly driven by interfacility practice variation rather than specific high-risk patient and/or tumor characteristics.

Sentinel lymph node biopsy versus axillary lymph node dissection in breast cancer patients undergoing mastectomy with one to two metastatic sentinel lymph nodes: sub-analysis of the SINODAR-ONE multicentre randomized clinical trial and reopening of enrolment

BACKGROUND

The initial results of the SINODAR-ONE randomized clinical trial reported that patients with T1-2 breast cancer and one to two macrometastatic sentinel lymph nodes treated with breast-conserving surgery, sentinel lymph node biopsy only, and adjuvant therapy did not present worse 3-year survival, regional recurrence, or distant recurrence rates compared with those treated with axillary lymph node dissection. To extend the recommendation of axillary lymph node dissection omission even in patients treated with mastectomy, a sub-analysis of the SINODAR-ONE trial is presented here.

METHODS

Patients with T1-2 breast cancer and no more than two metastatic sentinel lymph nodes undergoing mastectomy were analysed. After sentinel lymph node biopsy, patients were randomly assigned to receive either axillary lymph node dissection followed by adjuvant treatment (standard arm) or adjuvant treatment alone (experimental arm). The primary endpoint was overall survival. The secondary endpoint was recurrence-free survival.

RESULTS

A total of 218 patients were treated with mastectomy; 111 were randomly assigned to the axillary lymph node dissection group and 107 to the sentinel lymph node biopsy-only group. At a median follow-up of 33.0 months, there were three deaths (two deaths in the axillary lymph node dissection group and one death in the sentinel lymph node biopsy-only group). There were five recurrences in each treatment arm. No axillary lymph node recurrence was observed. The 5-year overall survival rates were 97.8 and 98.7 per cent in the axillary lymph node dissection treatment arm and the sentinel lymph node biopsy-only treatment arm, respectively (P = 0.597). The 5-year recurrence-free survival rates were 95.7 and 94.1 per cent in the axillary lymph node dissection treatment arm and the sentinel lymph node biopsy treatment arm, respectively (P = 0.821).

CONCLUSION

In patients with T1-2 breast cancer and one to two macrometastatic sentinel lymph nodes treated with mastectomy, the overall survival and recurrence-free survival rates of patients treated with sentinel lymph node biopsy only were not inferior to those treated with axillary lymph node dissection. To strengthen the conclusion of the trial, the enrolment of patients treated with mastectomy was reopened as a single-arm experimental study.

REGISTRATION NUMBER

NCT05160324 (http://www.clinicaltrials.gov).

Inequalities in the omission of axillary dissection in sentinel lymph node positive patients in the Netherlands: Innovative hospitals are early adopters of a de-escalating approach

During the last decade completion axillary lymph node dissection (cALND) was gradually omitted in sentinel lymph node positive (SLN+) breast cancer patients. However, adoption varies among hospitals. We analyzed factors associated with the omission of cALND in all Dutch SLN+ patients. As one of the focus hospital-related factors we defined "innovative" as the percentage of gene-expression profile (GEP) deployment within the indicated group of patients per hospital as a proxy for early adoption of innovations. cT1-2N0M0 SLN+ patients treated between 2011 and 2018 were selected from the Netherlands Cancer Registry. Hospitals were defined to be innovative based on their GEP use. Multivariable logistic regression (MLR) was performed to assess the relationship between innovative capacity, patient-, treatment- and hospital-related characteristics and cALND performance. 14 317 patients were included. Treatment in a hospital with high innovative capacity was associated with a lower probability of receiving cALND (OR 0.69, OR 0.46 and OR 0.35 in modestly, fairly and very innovative, respectively). Other factors associated with a lower probability of receiving a cALND were age 70 and 79 years and ≥79 years (ORs 0.59 [95% CI: 0.50-0.68] and 0.21 [95% CI: 0.17-0.26]) and treatment in an academic hospital (OR 0.41 [95% CI: 0.33-0.51]). Factors associated with an increased probability of undergoing cALND were HR-/HER2- tumors (OR 1.46 [95% CI: 1.19-1.80]), macrometastatic lymph node involvement (OR 6.37 [95% CI: 5.70-7.13]) and mastectomy (OR 4.57 [95% CI: 4.09-5.10]). Patients treated in a hospital that early adopted innovations were less likely to receive cALND. Our findings endorse the need for studies on barriers and facilitators of implementing innovations.

Unmeasured factors are associated with the use of completion lymph node dissection (CLND) in melanoma

BACKGROUND

Completion lymph node dissection (CLND) was the standard treatment for patients with melanoma with positive sentinel lymph nodes (SLN) until 2017 when data from the DeCOG-SLT and MLST-2 randomized trials challenged the survival benefit of this procedure. We assessed the contribution of patient, tumor and facility factors on the use of CLND in patients with surgically resected Stage III melanoma.

METHODS

Using the National Cancer Database, patients who underwent surgical excision and were found to have a positive SLN from 2012 to 2017 were included. A multivariable mixed-effects logistic regression model with a random intercept for the facility was used to determine the effect of patient, tumor, and facility variables on the risk of CLND. Reference effect measures (REMs) were used to compare the contribution of contextual effects (unknown facility variables) versus measured variables on the variation in CLND use.

RESULTS

From 2012 to 2017, the overall use of CLND decreased from 59.9% to 26.5% (p < 0.0001). Overall, older patients and patients with government-based insurance were less likely to undergo CLND. Tumor factors associated with a decreased rate of CLND included primary tumor location on the lower limb, decreasing depth, and mitotic rate <1. However, the contribution of contextual effects to the variation in CLND use exceeded that of the measured facility, tumor, time, and patient variables.

CONCLUSIONS

There was a decrease in CLND use during the study period. However, there is still high variability in CLND use, mainly driven by unmeasured contextual effects.

Surgical Management of the Axilla for Breast Cancer

This review discusses the contemporary surgical management of the axilla in patients with breast cancer. Surgical paradigms are highlighted by clinical nodal status at presentation and treatment approach, including upfront surgery and neoadjuvant systemic therapy settings. This review focuses on the increasing opportunities for de-escalating the extent of axillary surgery in the era of sentinel lymph node biopsy, while also reviewing the remaining indications for axillary clearance with axillary lymph node dissection.

Evaluation of adjuvant therapy for T1-2N1miM0 breast cancer without further axillary lymph node dissection

Background

For breast cancer (BC) with sentinel lymph node micrometastases (SLNMs), there are limited data to guide the selection of postoperative adjuvant therapy. This study aimed to identify target populations who might benefit most from adjuvant therapy and examine prognostic factors among patients with T1-2N1miM0 BC with one or two SLNMs who underwent sentinel lymph node biopsy (SLNB) alone.

Methods

There were 7,423 patients diagnosed with T1-2N1miM0 BC between 2010 and 2015, and patients with one or two SLNMs were extracted from the Surveillance, Epidemiology, and End Results database. All the patients underwent SLNB alone without further axillary lymph node dissection, and they were stratified according to adjuvant therapy. The statistical significance of categorical variables was analyzed using the χ ² test. Univariable and multivariable Cox analyses were used to analyze characteristics predictive of Breast-cancer-specific survival and overall survival (OS). Kaplan-Meier methods with the log-rank test was analyzed to compare survival difference between the different treatments.

Results

Adjuvant chemotherapy and radiotherapy improved 5-year OS rates. Multivariate analysis revealed that age ≥70 years, high grade, T2 stage, triple-negative subtype, and absence of radiotherapy were poor prognostic factors for OS. Patients who received breast-conserving surgery (BCS), and those with invasive ductal carcinoma (IDC), luminal A, luminal B, or basal-like subtype, and T1c or T2 stage benefited from adjuvant radiotherapy. Patients who received BCS, and those with IDC, luminal A subtype, and T1b, T1c, or T2 stage benefited from adjuvant chemotherapy.

Conclusion

Our findings provide a clinical evaluation of treatment choice after surgery, which may help clinicians make individualized clinical decisions.

Axillary lymph node dissection can be omitted in patients with limited clinically node-positive breast cancer: a National Cancer Database analysis

BACKGROUND

De-escalation of axillary surgery in breast cancer has progressively taken place when appropriate. Data supporting surgical de-escalation in patients with clinically node-positive (cN+) disease remains scarce. Here, survival among patients with cN+ T1-2 tumours undergoing sentinel lymph node biopsy (SLNB) and regional nodal irradiation (RNI) was investigated and compared with that among patients undergoing axillary lymph node dissection (ALND) with or without RNI.

METHODS

The National Cancer Data Base was used to identify three groups of patients with cN+ tumours according to axillary management among those treated between 2010 and 2016: patients who underwent SLNB and RNI (cN+ SLNB/RNI group); those who had ALND and RNI (cN+ ALND/RNI group); and those who had ALND alone (cN+ ALND/no RNI group). Patients who underwent neoadjuvant chemotherapy, and those who had stage IV breast cancer or pN2-3 disease were excluded.

RESULTS

A total of 12 560 patients met the inclusion criteria: 3030 in the cN+ SLNB/RNI, 5446 in the cN+ ALND/RNI, and 4084 in the cN+ ALND/no RNI group. The sizes of cN + SLNB/RNI and cN+ ALND/RNI groups increased over the study interval, whereas the cN+ ALND/no RNI group decreased in size (P < 0.001). There was a median of one positive node in the cN+ SLNB/RNI group and two nodes in the cN+ ALND/RNI and cN+ ALND/no RNI groups. The median number of nodes examined was three, 14, and 14, respectively (P < 0.001). Median follow-up was 57.9 (range 0.8-114) months. The overall survival rate was 97, 97, and 92 per cent respectively at two years, and 88, 86, and 78 per cent at five years (P < 0.001).

CONCLUSION

Patients with limited cN+ T1-2 breast cancer undergoing upfront SLNB and RNI have favourable survival outcomes that are not inferior to those of patients undergoing ALND with or without RNI. Prospective studies are warranted to assess locoregional control and long-term outcomes.

Radiotherapy or Surgery of the Axilla After a Positive Sentinel Node in Breast Cancer: 10-Year Results of the Randomized Controlled EORTC 10981-22023 AMAROS Trial

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.

PURPOSE

The European Organisation for Research and Treatment of Cancer 10981-22023 AMAROS trial evaluated axillary lymph node dissection (ALND) versus axillary radiotherapy (ART) in patients with cT1-2, node-negative breast cancer and a positive sentinel node (SN) biopsy. At 5 years, both modalities showed excellent and comparable axillary control, with significantly less morbidity after ART. We now report the preplanned 10-year analysis of the axillary recurrence rate (ARR), overall survival (OS), and disease-free survival (DFS), and an updated 5-year analysis of morbidity and quality of life.

METHODS

In this open-label multicenter phase III noninferiority trial, 4,806 patients underwent SN biopsy; 1,425 were node-positive and randomly assigned to either ALND (n = 744) or ART (n = 681).

RESULTS

Per intention-to-treat analysis, 10-year ARR cumulative incidence was 0.93% (95% CI, 0.18 to 1.68; seven events) after ALND and 1.82% (95% CI, 0.74 to 2.94; 11 events) after ART (hazard ratio [HR], 1.71; 95% CI, 0.67 to 4.39). There were no differences in OS (HR, 1.17; 95% CI, 0.89 to 1.52) or DFS (HR, 1.19; 95% CI, 0.97 to 1.46). ALND was associated with a higher lymphedema rate in updated 5-year analyses (24.5% v 11.9%; P < .001). Quality-of-life scales did not differ by treatment through 5 years. Exploratory analysis showed a 10-year cumulative incidence of second primary cancers of 12.1% (95% CI, 9.6 to 14.9) after ART and 8.3% (95% CI, 6.3 to 10.7) after ALND.

CONCLUSION

This 10-year analysis confirms a low ARR after both ART and ALND with no difference in OS, DFS, and locoregional control. Considering less arm morbidity, ART is preferred over ALND for patients with SN-positive cT1-2 breast cancer.

Axilla lymph node dissection can be safely omitted in patients with 1-2 positive sentinel nodes receiving mastectomy: a large multi-institutional study and a systemic meta-analysis

PURPOSE

This study aimed to evaluate whether axillary lymph node dissection (ALND) can be omitted in patients with 1-2 positive sentinel lymph nodes (SLNs) who received total mastectomy (TM).

METHODS

Consecutive breast cancer patients with 1-2 positive SLNs were retrospectively reviewed from a multi-institutional database. Patients were divided into sentinel lymph node biopsy (SLNB) group and ALND group. Administration of adjuvant chemotherapy and survival were compared between groups. To further verify the results, a meta-analysis was also conducted.

RESULTS

Among the 1161 enrolled patients, 893 (76.9%) received ALND and 268 (23.1%) underwent SLNB alone. Administration of chemotherapy was comparable between the two groups (91.1% vs. 90.6%, P = 0.798), which was consistent in TM (P = 0.638) and BCS cohort (P = 0.576). After a median follow-up of 36 months, no significant difference was observed between the two groups in recurrence-free survival (P = 0.583) regardless of surgery of breast. During further meta-analysis, 13 out of 4733 relative studies reported the association of axillary surgery and disease-free survival (DFS) or overall survival (OS) in 1-2 positive SLNs patients. Pooled analysis showed no difference in adjusted DFS (HR 0.84, 95% CI 0.70-1.02) or OS (HR 1.02, 95% CI 0.93-1.11) between SLNB and ALND groups. Survival benefit of ALND remained non-significant after restricting the analysis in four studies with patients only receiving BCS, or in three studies with patients only receiving TM.

CONCLUSION

Further ALND does not impact adjuvant chemotherapy administration or disease outcome in breast cancer patients with 1-2 positive SLNs treated with TM.

Extranodal extension, an international survey on its evaluation and reporting in breast cancer patients

Lymph node metastasis is the most important prognostic factor for breast cancer patients. In addition to the number of nodes involved and the largest metastatic focus, extranodal extension (ENE) is also used to subclassify breast cancer patients into different risk groups. More recently, pathologists are required to report the size/extent of ENE per the new CAP guideline, as it seems to be associated with more axillary nodal burden and/or a worse prognosis. Although the definition of ENE is largely understood and agreed upon among pathologists around the world, evaluation and reporting for the size of ENE are not. To understand current practice, we conducted an international survey among pathologists who are interested in breast pathology. A total of 70 pathologists responded. The results showed that (1) 98% of the participants reported the presence or absence of ENE and 61% also reported the size of ENE in millimeter (mm). (2) There was no uniform method of measuring the size of ENE; 47% measured the largest dimension regardless of orientation, while 30% measured the largest perpendicular distance from the capsule. (3) The most common factors affecting the accuracy in diagnosis of ENE are the presence of lymphovascular invasion (LVI), lack of capsule integrity, and the presence of fatty hilar or fatty replacement of a lymph node. (4) 71% felt that the H&E stain is adequate to evaluate ENE, deeper levels and IHC analysis for vascular and cytokeratin markers can be helpful if needed. (5) 75% agreed that there is an urgent need to standardize the measurement and reporting for ENE. Our survey highlights the variation in ENE evaluation and the need for its standardization in breast cancer patients with axillary node metastasis.

Impact of the ACOSOG Z0011 trial on surgical practice in Asian patients: trends in axillary surgery for breast cancer from a Korean Breast Cancer Registry analysis

Background

Since the publication of the Z0011 trial, practice-changing clinical guidelines for breast surgery have been developed. Although recent studies confirmed the feasibility of the Z0011 strategy in Asian populations, there has been no study on the trends of axillary surgery in Asian cohort. This study aimed to investigate the time trend of axillary surgery for breast cancer from a Korean Breast Cancer Registry to understand the impact of the Z0011 trial in Asian patients.

Methods

We collected prospectively constructed data from the nationwide Korean Breast Cancer Registry (KBCR). We identified patients who underwent sentinel node biopsy followed by breast-conserving surgery from 2011 to 2018 and were found to have pathological stage T1-2N1-3M0 disease. Regression analyses were performed to compare the downward trend of axillary lymph node dissection (ALND) in Korean cohort with that previously reported in a Dutch cohort.

Results

From KBCR data, 7478 patients met the inclusion criteria. The proportion of ALND significantly decreased from 2011 (76.6%) to 2018 (47.5%). Multivariate analysis revealed that earlier years at diagnosis, larger tumor size, and lymphatic invasion were associated with a higher odds ratio of performing ALND. Compared to the Dutch cohort, the downward trend of ALND in Korea was significantly more gradual (annual percent change: 37.2 vs. 5.8%, p < 0.001).

Conclusions

This study demonstrated a downward trend of ALND in Korean patients with breast cancer. However, the rate of decrease was significantly slower than that in the Dutch cohort.

Addressing the problem of overtreatment in breast cancer

INTRODUCTION

As breast cancer treatment options have multiplied and biologic diversity within breast cancer has been recognized, the use of the same treatment strategies for patients with early-stage and favorable disease, and for those with biologically aggressive disease, has been questioned. In addition, as patient-reported outcome measures have called attention to the morbidity of many common treatments, and as the cost of breast cancer care has continued to increase, reduction in the overtreatment of breast cancer has assumed increasing importance.

AREAS COVERED

Here we review selected aspects of surgery, radiation oncology, and medical oncology for which scientific evidence supports de-escalation for invasive carcinoma and ductal carcinoma in situ, and assess strategies to address overtreatment.

EXPERT OPINION

The problems of breast cancer overtreatment we face today are based on improved understanding of the biology of breast cancer and abandonment of the 'one-size-fits-all' approach. As breast cancer care becomes increasingly complex, and as our knowledge base continues to increase exponentially, these problems will only be magnified in the future. To continue progress, the move must be made from advocating the maximum-tolerated treatment to advocating the minimum-effective one.

De-escalation in breast cancer surgery

In recent years, several trials of breast cancer treatment have failed to demonstrate a survival benefit for some previously routine surgical therapies in selected patient groups. As each of these therapeutic approaches has been deemed of low value deimplementation has varied significantly. This demonstrates that effective de-escalation in breast cancer surgery relies on more than the availability of data from randomized controlled trials and other high-quality evidence, but is also influenced by various stakeholders, social expectations, and environmental contexts.

Avoiding unnecessary intraoperative sentinel lymph node frozen section biopsy of patients with early breast cancer

Purpose

After the publication of the ACOSOG (American College of Surgeons Oncology Group) Z0011 trial, the rate of axillary lymph node dissection has reduced. Thus, the need for intraoperative frozen section biopsy of sentinel lymph nodes (SLNs) has become controversial. We identified patients for whom intraoperative SLN frozen section biopsy could be omitted and found that frozen section biopsy rate can be reduced.

Methods

We reviewed the records of patients with tumors ≤5 cm in diameter who underwent breast-conserving surgery between January 2013 and December 2019 at Seoul St. Mary’s Hospital. Clinicopathological and imaging characteristics were compared according to number of positive SLNs (0–2 SLNs positive vs. ≥3 SLNs positive).

Results

A total of 1,983 patients were included in this study. Thirty-two patients (1.6%) had at least 3 positive SLNs. Patients with ≥3 positive SLNs had significantly larger tumors and were more frequently high-grade tumors (P < 0.001 and P = 0.002, respectively). Identification of suspicious lymph nodes on imaging studies was also associated with the presence of ≥3 positive SLNs (hazard ratio, 11.54; 95% confidence interval, 4.42–30.10). All patients with none or only 1 suspicious lymph node on any imaging modality (n = 647, 32.6%) had 0–2 positive SLNs. Also, among patients with clinical T1-stage tumors and at least 2 suspicious lymph nodes on only 1 imaging modality (n = 514, 25.9%), only 2 cases had ≥3 positive SLNs.

Conclusion

We found that intraoperative SLN frozen biopsy could be omitted in patients using tumor size and axillary lymph node status on imaging modality.

Stepwise Limited Axillary Lymph Node Dissection Based on Lymphatic Drainage from the Breast to Decrease Breast Cancer-Related Lymphedema: A Randomized Controlled Trial

BACKGROUND

Comprehensive axillary surgery is associated with an elevated rate of morbidity. This trial aimed to demonstrate the feasibility of axillary dissection of lymph nodes from the breast (bALND) for the purpose of limiting the extent of surgery.

METHODS

Patients enrolled from two tertiary referral centers from September 2018 to September 2019 were randomly allocated to two groups: bALND and standard axillary lymph node dissection (sALND). In the bALND group, the sentinel lymph node was filled with 0.1 ml methylene blue before resection. Then, bALND based on lymphatic drainage was subsequently performed. Lymph nodes at each breast lymphatic level and lymph nodes at Berg levels were sent for separate pathological examination. Arm lymphedema, locoregional recurrence, and distant metastasis were documented.

RESULTS

In the bALND group, lymphatic vessels and subsequent-echelon lymph nodes from the breast were stained blue after injection of methylene blue in 404 (89.0%, 404/454) cases, and 57.8% (228/394) of the patients harbored fewer than four metastatic nodes. With a median follow-up of 18 months, the incidence of arm lymphedema was 6.6% (26/394) in the bALND group versus 13.7% (60/438) in the sALND group (p = 0.008), while regional recurrence presented no difference between the two surgical procedures (0.76% vs 0.68%, p = 0.896).

CONCLUSION

For node-positive breast cancer patients, bALND based on lymphatic drainage is a less radical axillary surgery that can eliminate morbidity without impairing cancer control.

The Dilemma After an Unforeseen Positive Sentinel Node in Primary Breast Cancer: Is Completion Axillary Dissection Necessary?

BACKGROUND

In the majority of cases, the sentinel node is the only positive node in the axilla and completion ALND (cALND) is a futile procedure. However, refraining from cALND will lead to less accurate staging and, possibly, undertreatment. To help resolve this dilemma, we examined the clinical value of cALND in staging and determining adjuvant treatment.

METHODS

In a retrospective cohort, all consecutive patients over a five-year period with primary breast cancer who received ALND were identified and grouped based on timing of ALND. Total nodal yield and positive lymph nodes were defined and factors with possible impact identified. In the case of cALND, N-status upstaging and possible impact on adjuvant treatment were studied in detail.

RESULTS

A total of 280 patients were selected of whom 204 underwent primary ALND (pALND) and 76 cALND. pALND resulted in a significantly higher total nodal yield and more positive nodes when compared to cALND (p = 0.003, and p < 0.001, respectively). Neoadjuvant chemotherapy (NAC) had no effect on total nodal yield (p = 0.413), but resulted in fewer positive nodes (p < 0.001). Due to the results of cALND, only 11 patients (14%) had upstaging of N-status. All these patients were advised more extensive adjuvant radiotherapy.

CONCLUSION

In the majority of patients, cALND does not lead to upstaging. cALND should be performed only after a careful discussion with the patient about the pros and cons of this procedure, and most probably only in the presence of multiple risk factors for axillary disease in the absence of systemic therapy.

Breast and axillary surgery in malignant breast disease: a review focused on literature of 2018 and 2019

PURPOSE OF REVIEW

There have been fundamental changes in the surgical approach to breast cancer management over the last decades. The primary objective of achieving locoregional control, however, remains unchanged.

RECENT FINDINGS

In addition to strategies optimizing systemic treatment and radiotherapy, current discussions focus on improving the surgical approach to breast cancer. Especially in view of the increasingly pivotal role of neoadjuvant chemotherapy NAT/NAC (NACT), gauging the extent of tissue removal in the breast and the width of resection margins in breast-conserving surgery is highly important, as is the extent of axillary surgery. Although sentinel lymph node (SLN)-positive patients always underwent axillary lymph node dissection in the past, this paradigm has been challenged in recent years. Targeted axillary dissection (TAD) has emerged as a new staging option in biopsy-proven node-positive patients who convert to clinical node negativity (cN0) after NACT. TAD combines the removal of the SLN and of the target lymph node marked prior to NACT. The accuracy of axillary staging both before and after NACT plays an important role for prognostication and multidisciplinary treatment plans, while its extent has significant effects on patients' arm morbidity and quality of life.

SUMMARY

The current review focuses on recent evidence regarding surgical management of the breast and axilla in patients with primary breast cancer based on a PubMed and EMBASE literature search for publication years 2018 and 2019.

Minimize the extent and morbidity of axillary dissection for node-positive breast cancer patients: implementation of axillary lymph node dissection based on breast lymphatics level

Background

Breast cancer-related lymphedema (BCRL) is associated with extensive axillary dissection. Axillary lymph node dissection (ALND) based on breast lymphatics level (BLL) was proposed to minimize the surgical extent for node-positive breast cancer patients.

Methods

A total of 156 consecutive sentinel lymph node-positive (SLN+) or clinically node-positive (cN+) patients underwent sentinel lymph node biopsy (SLNB) with indocyanine green and methylene blue (MB). The SLNs were injected with 0.1 ml MB before removal, and a standard ALND was subsequently performed. The nodes adjacent to the blue-stained axillary lymph nodes from the breast (bALNs) were sent for pathological examination separately by resecting serial tissue every 0.5 cm away from the marginal blue-stained bALNs. Then, a pilot study comparing ALND based on BLL and standard ALND was performed.

Results

BLL were successfully identified in 20 SLN+ (100%) and 134 cN+ (98.5%) patients. The median number of BLL was four, ranging from three to six. A horizontal line 1.0 cm away from the superior blue-stained bALN and a vertical line 1.0 cm away from the medial blue-stained bALN formed BLL II, III, and IV. All of the additional positive nodes were within 1.0 cm of the blue-stained bALNs. The minimized axillary dissection should resect upwards from the lowest BLL that contains the first confirmed negative blue-stained bALNs. In the pilot study, no patient developed axillary recurrence.

Conclusion

The ALND surgical procedure based on BLL could minimize the surgical extent for pathological node-positive breast cancer patients and potentially reduce the BCRL rate.

Trial registration

ChiCTR1800014247.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08024-y.

Clinical Practice Status of Sentinel Lymph Node Biopsy for Early-Stage Breast Cancer Patients in China: A Multicenter Study

Background

Sentinel lymph node biopsy (SLNB) was introduced over 30 years ago, but the application of SLNB in China is unclear. This study aimed to explore the real-world implementation of SLNB among early-stage breast cancer patients in China.

Methods

A multi-center, retrospective study was conducted among primary breast cancer patients from 37 hospitals in China in 2018. Their clinical data were collected and analyzed, including the implementation status of SLNB in China, subsequent processing of sentinel lymph nodes (SLNs) containing metastases, and the effect of neoadjuvant chemotherapy (NAC) on SLNB.

Results

SLNB surgery was performed on 43.5% of early-stage breast cancer patients in China and 11,942 patients who underwent SLNB were enrolled in this study. The majority of SLNBs were performed using a single mapping agent. A combination of blue dye and radiotracer or fluorescence imaging was used in only 14.9% of patients. The mean (SD) number of resected SLNs was 4.0 (2.1). For the patients with 1 or 2 positive SLNs, 83.0% of them continued to receive axillary lymph node dissection (ALND), while others did not. For the patients with three or more positive SLNs, 97.2% of them continued to receive ALND, among which 82.9% accepted radiotherapy simultaneously. Of the patients who underwent SLN surgery, 5.5% (654/11,942) were receiving NAC. Among them, 51.9% received SLNB before NAC, and the rest received SLNB after NAC. In biopsy-proven positive nodes, 64.7% positive SLNs turned negative after NAC.

Conclusion

SLNB has been promoted in China, but it is not widely used compared to in developed countries. Furthermore, the usage of the dual tracer technique in SLNB is not high. Chinese breast surgeons are more conservative regarding the omission of ALND in 1 or 2 SLNs-positive patients.

Analyzing non-sentinel axillary metastases in patients with T3-T4 cN0 early breast cancer and tumor-involved sentinel lymph nodes undergoing breast-conserving therapy or mastectomy

Purpose

In the ACOSOG Z0011 trial, completing axillary lymph node dissection (cALND) did not benefit patients with T1–T2 cN0 early breast cancer and 1–2 positive sentinel lymph nodes (SLN) undergoing breast-conserving surgery (BCT). This paper reports cALND rates in the clinical routine for patients who had higher (T3–T4) tumor stages and/or underwent mastectomy but otherwise met the ACOSOG Z0011 eligibility criteria. Aim of this study is to determine cALND time trends and non-sentinel axillary metastases (NSAM) rates to estimate occult axillary tumor burden.

Methods

Data were included from patients treated in 179 German breast cancer centers between 2008 and 2015. Time-trend rates were analyzed for cALND of patients with T3–T4 tumors separated for BCT and mastectomy and regarding presence of axillary macrometastases or micrometastases.

Results

Data were available for 188,909 patients, of whom 19,009 were identified with 1–2 positive SLN. Those 19,009 patients were separated into 4 cohorts: (1) Patients with T1–T2 tumors receiving BCT (ACOSOG Z0011 eligible; n = 13,741), (2) T1–T2 with mastectomy (n = 4093), (3) T3–T4 with BCT (n = 269), (4) T3–T4 with mastectomy (n = 906). Among patients with T3–T4 tumors, cALND rates declined from 2008 to 2015: from 88.2 to 62.6% for patients receiving mastectomy and from 96.6 to 58.1% in patients receiving BCT. Overall rates for any NSAM after cALND for cohorts 1–4 were 33.4%, 42.3%, 46.9%, 58.8%, respectively.

Conclusions

The cALND rates have decreased substantially in routine care in patients with ‘extended’ ACOSOG Z0011 eligibility criteria. Axillary tumor burden is higher in these patients than in the ACOSOG Z0011 trial.

Axillary Management in Women with Early Breast Cancer and Limited Sentinel Node Metastasis: A Systematic Review and Metaanalysis of Real-World Evidence in the Post-ACOSOG Z0011 Era

BACKGROUND

After the publication of the Z0011 trial, the American Society of Clinical Oncology published an updated clinical practice guideline stating that clinicians should not recommend axillary lymph node dissection (ALND) for early-stage breast cancer patients with the involvement of one or two sentinel lymph nodes (SLNs). However, these recommendations have been challenged because they were mainly based on data from limited studies. The aim of the current study is to systematically compare the real-world outcomes of SLN biopsy (SLNB) alone and SLNB + ALND in patients with early-stage breast cancers and limited positive SLN metastasis in the post-Z0011 era PATIENTS AND METHODS: We searched articles in the PubMed, EMBASE, and Cochrane library databases. The primary endpoints were overall survival (OS) and disease-free survival (DFS). The secondary endpoints were recurrence rate and the incidence of lymphedema.

RESULTS

One randomized controlled trial and six retrospective studies with 8864 patients were retrieved. For patients with early-stage breast cancer with one or two SLN metastases, receiving SLNB alone showed no significant difference in OS, DFS, and recurrence rate compared with receiving SLNB + ALND. The incidence of lymphedema in patients who received SLNB alone was significantly lower than those who received SLNB + ALND (odds ratio 1.95, 95% confidence interval 1.02-3.71).

CONCLUSIONS

Current real-world evidence proved that the Z0011 strategy is safe with respect to survival outcomes and effective in reducing the incidence of lymphedema. ALND should be avoided in patients with early-stage breast cancer with one or two SLN metastases in the post-Z0011 era.

Evaluating the impact of axillary dissection on recurrence-free survival by extent of nodal disease in invasive lobular carcinoma of the breast

PURPOSE

Clinical trials have shown that axillary lymph node dissection (ALND) can be avoided for many breast cancer patients with limited nodal involvement. However, whether its omission is safe for those with invasive lobular carcinoma (ILC) is still questioned. We sought to evaluate the impact of ALND on recurrence-free survival (RFS) by extent of nodal disease in patients with ILC.

METHODS

We performed a retrospective, cross-sectional analysis of ILC patients treated between 1990 and 2019 at our institution. Patients underwent either breast conservation surgery (BCS) or mastectomy. We used univariate and multivariate statistics in Stata 14.2 to evaluate associations between extent of axillary surgery and time to recurrence stratified by nodal burden.

RESULTS

Of 520 cases, 387 (78.4%) were node negative, 74 (14.9%) had 1-2 positive nodes, and 59 (11.4%) had three or more positive nodes. Most patients (93.3%) had hormone receptor-positive disease, and 94.8% had low or intermediate-grade tumors. The rate of ALND significantly decreased over time (p < 0.002). Using a multivariate model, there was no significant difference in RFS estimates based on receipt of ALND (HR = 0.53, 95% CI 0.17-1.64, p = 0.27), which also held true for patients with 1-2 positive nodes using a test of interaction (HR = 0.91, 95% CI 0.12-6.76, p = 0.92).

CONCLUSIONS

These findings support the safety of omitting ALND in selected patients with ILC. Further studies of axillary management in ILC and imaging tools to predict nodal involvement and therapeutic response are warranted.

National Trend of Axillary Management in Clinical T3/T4 N0 Patients Having Breast Conserving Therapy

BACKGROUND

The ACOSOG Z0011 trial has essentially eliminated axillary lymph node dissection (ALND) in breast conserving therapy (BCT) patients with clinical T1/T2 and 1-2 positive sentinel lymph nodes (SLNs). Currently, ALND is recommended for positive SLNs unless ACOSOG Z0011 criteria are applicable. We aimed to assess the national trends and axillary management before and after the publication of ACOSOG Z0011 for larger tumors.

METHODS

An IRB-approved study evaluated the National Cancer Database from 2006 to 2016. Women with clinical T3/T4, N0 who otherwise fit ACOSOG Z0011 criteria were included. Neoadjuvant systemic therapy or known nodal disease was excluded. Clinicopathologic data were compared between two timeframes based on ACOSOZ Z0011 publication and by axillary management. Patients were categorized into SLNB alone (1-5 lymph nodes examined) and ALND (≥10 lymph nodes examined) groups.

RESULTS

A total of 230 women fit inclusion criteria, of whom 36% underwent ALND. ALND use decreased from 54% in 2006 to 14% in 2016 (P < 0.01). Comparing ALND to SLNB alone within the pre-Z0011 era, comprehensive community cancer programs had higher proportions of ALND, whereas academic centers had higher rates of SLND alone (P = 0.03). Comparing similar axillary management between eras, SLNB-alone patients in the post-Z0011 era had higher pT and pN stages, were less likely to be Her2 positive, and were more likely to receive systemic treatment.

CONCLUSIONS

There is a national trend to forgo ALND in women who have tumors larger than those included in the Z0011 criteria without any clear clinicopathologic indications.

Assessment of Technical Skills in Axillary Lymph Node Dissection

OBJECTIVE

A simulator to enable safe practice and assessment of ALND has been designed, and face, content and construct validity has been investigated.

SUMMARY AND BACKGROUND DATA

The reduction in the number of ALNDs conducted has led to decreased resident exposure and confidence.

METHODS

A cross-sectional multicenter observational study was carried out between July 2017 and August 2018. Following model development, 30 surgeons of varying experience (n = "experts,' n = 11 "senior residents,' and n = 10 "junior residents") were asked to perform a simulated ALND. Face and content validity questionnaires were administered immediately after ALND. All ALND procedures were retrospectively assessed by 2 attending breast surgeons, blinded to operator identity, using a video-based assessment tool, and an end product assessment tool.

RESULTS

Statistically significant differences between groups were observed across all operative subphases on the axillary clearance assessment tool (P < 0.001). Significant differences between groups were observed for overall procedure quality (P < 0.05) and total number of lymph nodes harvested (P < 0.001). However, operator grade could not be distinguished across other end product variables such as axillary vein damage (P = 0.864) and long thoracic nerve injury (P = 0.094). Overall, participants indicated that the simulator has good anatomical (median score >7) and procedural realism (median score >7).

CONCLUSIONS

Video-based analysis demonstrates construct validity for ALND assessment. Given reduced ALND exposure, this simulation is a useful adjunct for both technical skills training and formative Deanery or Faculty administered assessments.

Disparities in the Use of Sentinel Lymph Node Dissection for Early Stage Breast Cancer

BACKGROUND

Clinical trials have long established the long-term safety of omitting axillary lymph node dissection (ALND) after sentinel lymph node dissection (SLND) in patients with clinically node-negative early stage breast cancer. The variations in utilization of SLND and ALND in this patient population, however, are currently unknown.

METHODS

Adult female patients (40 years and older) within the National Cancer Database diagnosed with breast cancer between January 2013 and December 2015, who had clinical T1-T2 and N0 disease, and who underwent either SLND (with or without subsequent ALND) or ALND were included. Differences in utilization across race, ethnicity, insurance type, facility, and residential characteristics were assessed using multivariable logistic regression.

RESULTS

Overall, 271,689 patients were included, of which 26,527 (10%) received ALND and 245,162 (90%) underwent SLND. After adjusting for demographics and cancer characteristics, black (odds ratio [OR], 1.11; 95% confidence interval [95% CI], 1.06-1.17) and Hispanic women (OR, 1.16; 95% CI, 1.10-1.24) were more likely to receive ALND. Patients without health insurance (OR, 1.33; 95% CI, 1.19-1.47), compared with private health insurance, and those receiving treatment at community cancer centers (OR, 1.60; 95% CI, 1.53-1.67), compared with academic/research centers, were also more likely to receive ALND.

CONCLUSIONS

Although the vast majority of women undergo SLND, significant disparities exist in its utilization for early stage breast cancer, with traditionally underserved patients receiving unwarranted extensive axillary surgery. Increased patient and surgeon education is needed to decrease variations in care that can affect patient's quality of life.

Validating the ACOSOG Z0011 Trial Result: A Population-Based Study Using the SEER Database

The Z0011 trial demonstrated that axillary lymph node dissection (ALND) could be omitted in spite of 1-2 metastatic sentinel lymph nodes. This study aimed to validate the results on a population-based database. The Surveillance, Epidemiology, and End Results (SEER) database was searched for patients comparable to the Z0011 participants. The type of axillary surgery was estimated using the total number of examined axillary lymph nodes (ALNs). Breast cancer-specific mortality (BCSM) was compared between patients with ≥10 ALNs (the sentinel lymph node dissection (SLND) and ALND group, or "SLND + ALND group") and patients with one or two ALNs (the "SLND group"). During 2010-2015, the SEER database included 7077 and 6620 patients categorized in the SLND group and the SLND + ALND group, respectively. Death was observed for 515 patients (7.3%) in the SLND group and 589 patients (8.9%) in the SLND + ALND group based on a median follow-up of 41 months. After propensity-score matching, the adjusted hazard ratio for BCSM in the SLND group (vs. the SLND + ALND group) was 1.038 (95% confidence interval: 0.798-1.350). Regardless of the SLND criteria, the outcomes were not significantly different between the two groups. This retrospective cohort study of Z0011-comparable patients revealed that ALND could be omitted based on the Z0011 strategy, even among patients with ≤2 dissected ALNs.

De-escalation of axillary surgery in breast cancer patients treated in the neoadjuvant setting: a Dutch population-based study

PURPOSE

An overall trend is observed towards de-escalation of axillary surgery in patients with breast cancer. The objective of this study was to evaluate this trend in patients treated with neoadjuvant systemic therapy (NST).

METHODS

Patients with cT1-4N0-3 breast cancer treated with NST (2006-2016) were selected from the Netherlands Cancer Registry. Patients were classified by clinical node status (cN) and type of axillary surgery. Uni- and multivariable logistic regression analyses were performed to determine the clinicopathological factors associated with performing ALND in cN+ patients.

RESULTS

A total of 12,461 patients treated with NST were identified [5830 cN0 patients (46.8%), 6631 cN+ patients (53.2%)]. In cN0 patients, an overall increase in sentinel lymph node biopsy (SLNB) only (not followed by ALND) was seen from 11% in 2006 to 94% in 2016 (p < 0.001). SLNB performed post-NST increased from 33 to 62% (p < 0.001). In cN+ patients, an overall decrease in ALND was seen from 99% in 2006 to 53% in 2016 (p < 0.001). Age (OR 1.01, CI 1.00-1.02), year of diagnosis (OR 0.47, CI 0.44-0.50), HER2-positive disease (OR 0.62, CI 0.52-0.75), clinical tumor stage (T2 vs. T1 OR 1.32, CI 1.06-1.65, T3 vs. T1 OR 2.04, CI 1.58-2.63, T4 vs. T1 OR 6.37, CI 4.26-9.50), and clinical nodal stage (N3 vs. N1 OR 1.65, CI 1.28-2.12) were correlated with performing ALND in cN+ patients.

CONCLUSIONS

ALND decreased substantially over the past decade in patients treated with NST. Assessment of long-term prognosis of patients in whom ALND is omitted after NST is urgently needed.

Axillary management for young women with breast cancer varies between patients electing breast-conservation therapy or mastectomy

PURPOSE

Axillary treatment strategies for the young woman with early-stage, clinically node-negative breast cancer undergoing upfront surgery found to have 1-3 positive sentinel lymph nodes (SLNs) differ significantly after BCT and mastectomy. Here we compare axillary lymph node dissection (ALND) and regional nodal irradiation (NRI) rates between women electing breast-conservation therapy (BCT) versus mastectomy.

METHODS

From 2010 to 2016, women age < 50 years with clinical T1-T2N0 breast cancer having upfront surgery and found to have a positive SLN were identified. ALND and/or NRI receipt were compared between groups.

RESULTS

192 women undergoing BCT and 165 undergoing mastectomy were identified (median age: 44 years). 5.2% (10/192) of women undergoing BCT had an ALND versus 87% (144/165) of women undergoing mastectomy (p < 0.01). NRI was given to 48% (78/165) of mastectomy patients compared to 30% (57/192) of BCT patients (p < 0.01). Of the 75 mastectomy patients with 1-2 total positive lymph nodes after completion ALND, 44% received NRI. Women undergoing mastectomy were significantly more likely to receive both ALND and NRI than women undergoing BCS (45% vs 6%, p < 0.01).

CONCLUSION

Young cT1-2N0 breast cancer patients found to have 1-3 SLN metastases received ALND, NRI, and combined ALND/NRI more frequently if they elected mastectomy over BCT. Use of both ALND and postmastectomy radiotherapy (PMRT) in this population could be reduced in the future by omitting ALND in patients for whom the need for PMRT is clear with the finding of 1-2 SLN metastases.

Management of the axilla in patients with breast cancer and positive sentinel lymph node biopsy: An evidence-based update in a European breast center

The surgical approach to the axilla in breast cancer has been a controversial issue for more than three decades. Data from recently published trials have provided practice-changing recommendations in this scenario. However, further controversies have been triggered in the surgical community, resulting in heterogeneous diffusion of these recommendations. The development of clinical guidelines for the management of the axilla in patients with breast cancer is a work in progress. A multidisciplinary team discussion was held at the research hospital Policlinico San Matteo from the Università degli Studi di Pavia with the aim to update recommendations for the management of the axilla in patients with breast cancer. An evidence-based approach is presented. Our multidisciplinary panel determined that axillary dissection after a positive sentinel lymph node biopsy may be avoided in cN0 patients with micro/macrometastasis to ≤2 sentinel nodes, with age ≥40y, lesions ≤3 cm, who have not received neoadjuvant chemotherapy and have planned breast conservation (BCS) with whole breast radiotherapy (WBRT). Cases with gross (>2 mm) ECE in SLNs are evaluated on individual basis for completion ALND, axillary radiotherapy or omission of both. Patients fulfilling the criteria listed above who undergo mastectomy, may also avoid axillary dissection after multidisciplinary discussion of individual cases for consideration of axillary irradiation. Women 70 years or older with hormone receptors positive invasive lesions ≤3 cm, clinically negative nodes, and serious or multiple comorbidities who undergo BCS with WBRT, may forgo axillary staging/surgery (if mastectomy or larger tumor, comorbidities and life expectancy are taken into account).

Nationwide population-based study of the impact of immediate breast reconstruction after mastectomy on the timing of adjuvant chemotherapy

BACKGROUND

Initiation of adjuvant chemotherapy within 6-12 weeks after mastectomy is recommended by guidelines. The aim of this population-based study was to investigate whether immediate breast reconstruction (IBR) after mastectomy reduces the likelihood of timely initiation of adjuvant chemotherapy.

METHODS

All patients with breast cancer who had undergone mastectomy and adjuvant chemotherapy between 2012 and 2016 in the Netherlands were identified. Time from surgery to adjuvant chemotherapy was categorized as within 6 weeks or after more than 6 weeks, within 9 weeks or after more than 9 weeks, and within 12 weeks or after more than 12 weeks. The impact of IBR on the initiation of adjuvant chemotherapy for these three scenarios was estimated using propensity score matching to adjust for treatment by indication bias.

RESULTS

A total of 6300 patients had undergone primary mastectomy and adjuvant chemotherapy, of whom 1700 (27·0 per cent) had received IBR. Multivariable analysis revealed that IBR reduced the likelihood of receiving adjuvant chemotherapy within 6 weeks (odds ratio (OR) 0·76, 95 per cent c.i. 0·66 to 0·87) and 9 weeks (0·69, 0·54 to 0·87), but not within 12 weeks (OR 0·75, 0·48 to 1·17). Following propensity score matching, IBR only reduced the likelihood of receiving adjuvant chemotherapy within 6 weeks (OR 0·95, 0·90 to 0·99), but not within 9 weeks (OR 0·97, 0·95 to 1·00) or 12 weeks (OR 1·00, 0·99 to 1·01).

CONCLUSION

Postmastectomy IBR marginally reduced the likelihood of receiving adjuvant chemotherapy within 6 weeks, but not within 9 or 12 weeks. Thus, IBR is not contraindicated in patients who need adjuvant chemotherapy after mastectomy.

Lobular Histology Does Not Predict the Need for Axillary Dissection Among ACOSOG Z0011-Eligible Breast Cancers

BACKGROUND

The American College of Surgeons Oncology Group (ACOSOG) Z0011 trial demonstrated that axillary lymph node dissection (ALND) may be omitted for women with two or fewer positive sentinel nodes (SLNs) undergoing breast-conservation therapy (BCT). Lobular histology comprises a minority of patients, and applicability to these discohesive cancers has been questioned.

METHODS

From August 2010 to March 2017, patients undergoing BCT for cT1-2N0 cancer with positive SLNs were prospectively managed with ALND for three or more positive SLNs or gross extracapsular extension (ECE). In this study, clinicopathologic characteristics and nodal burden were compared between pure/mixed invasive lobular cancer (ILC) and invasive ductal cancer (IDC) patients.

RESULTS

Among 813 consecutive patients, 104 (12.8%) had ILC and 709 (87.2%) had IDC. ILC was more often multifocal and low grade, and less frequently had lymphovascular invasion (all p < 0.001). ILC more often had SLN macrometastases (81.7% ILC vs. 69.4% IDC; p = 0.01) and more than 2 mm of ECE (30.8% ILC vs. 19.5% IDC; p = 0.03), but the proportions of cases with three or more positive SLNs were similar in the two groups (14.4% ILC vs. 9.9% IDC; p = 0.2). The ALND procedure was performed for 20 ILC patients (19.2%) compared with 97 IDC patients (13.7%) (p = 0.2). Additional positive nodes were found in 80% of the ILC patients versus 56.7% of the IDC patients (p = 0.09). The ALND and nodal burden rates were similar in the estrogen receptor-positive (ER+) subset analysis. In the multivariable analysis, lobular histology (p = 0.03) and larger tumors (p = 0.03) were associated with additional positive nodes. During a median follow-up period of 42 months, there were no isolated axillary recurrences.

CONCLUSIONS

Despite a higher proportion of SLN macrometastases and association with more positive nodes at ALND, lobular histology does not predict the need for ALND. ALND is not indicated on the basis of histology among patients otherwise meeting Z0011 criteria.

Artificial neural network models to predict nodal status in clinically node-negative breast cancer

BACKGROUND

Sentinel lymph node biopsy (SLNB) is standard staging procedure for nodal status in breast cancer, but lacks therapeutic benefit for patients with benign sentinel nodes. For patients with positive sentinel nodes, individualized surgical strategies are applied depending on the extent of nodal involvement. Preoperative prediction of nodal status is thus important for individualizing axillary surgery avoiding unnecessary surgery. We aimed to predict nodal status in clinically node-negative breast cancer and identify candidates for SLNB omission by including patient-related and pathological characteristics into artificial neural network (ANN) models.

METHODS

Patients with primary breast cancer were consecutively included between January 1, 2009 and December 31, 2012 in a prospectively maintained pathology database. Clinical- and radiological data were extracted from patient's files and only clinically node-negative patients constituted the final study cohort. ANN-based models for nodal prediction were constructed including 15 risk variables for nodal status. Area under the receiver operating characteristic curve (AUC) and Hosmer-Lemeshow goodness-of-fit test (HL) were used to assess performance and calibration of three predictive ANN-based models for no lymph node metastasis (N0), metastases in 1-3 lymph nodes (N1) and metastases in ≥ 4 lymph nodes (N2). Linear regression models for nodal prediction were calculated for comparison.

RESULTS

Eight hundred patients (N0, n = 514; N1, n = 232; N2, n = 54) were included. Internally validated AUCs for N0 versus N+ was 0.740 (95% CI = 0.723-0.758); median HL was 9.869 (P = 0.274), for N1 versus N0, 0.705 (95% CI = 0.686-0.724; median HL: 7.421; P = 0.492) and for N2 versus N0 and N1, 0.747 (95% CI = 0.728-0.765; median HL: 9.220; P = 0.324). Tumor size and vascular invasion were top-ranked predictors of all three end-points, followed by estrogen receptor status and lobular cancer for prediction of N2. For each end-point, ANN models showed better discriminatory performance than multivariable logistic regression models. Accepting a false negative rate (FNR) of 10% for predicting N0 by the ANN model, SLNB could have been abstained in 27.25% of patients with clinically node-negative axilla.

CONCLUSIONS

In this retrospective study, ANN showed promising result as decision-supporting tools for estimating nodal disease. If prospectively validated, patients least likely to have nodal metastasis could be spared SLNB using predictive models.

TRIAL REGISTRATION

Registered in the ISRCTN registry with study ID ISRCTN14341750 . Date of registration 23/11/2018. Retrospectively registered.

Effect of the American College of Surgeons Oncology Group Z0011 trial on axillary management in breast cancer patients in the Australian setting

The American College of Surgeons Oncology Group Z0011 Trial demonstrated that early breast cancer patients with positive axillary sentinel lymph nodes treated with breast-conserving surgery and breast radiotherapy had no additional oncologic benefit of proceeding to an axillary lymph node dissection (ALND). The extent to which practice has changed in Australia remains unclear. The aim of this study was to investigate the effect of the Z0011 trial on the management of positive axillary sentinel nodes at an Australian institutional level. We reviewed all breast cancer cases treated at the Sydney Adventist Hospital over a 10-year period from 1 January 2008 to 31 December 2017. Patients who fulfilled the Z0011 trial criteria were selected. These patients were divided into two groups according to the year of surgery, before and after 1 January 2011 when the Z0011 study was published. Clinicopathologic data and axillary surgical management were compared. Of the 237 patients fulfilling the Z0011 trial criteria, there were 73 patients before and 158 patients after 1 January 2011. In the earlier group the rate of proceeding to an ALND following a positive sentinel node was 78.1% compared to 43.7% in the latter group (P < 0.0001). There was a significant decline in the rate of ALND over this 10-year period (r = -0.79, P = 0.006). The Z0011 trial has influenced the surgical management of the axilla leading to a significant reduction in the rate of an ALND in patients fulfilling the Z0011 trial criteria at our institution.

The impact of chemotherapy sequence on survival in node-positive invasive lobular carcinoma

BACKGROUND AND OBJECTIVES

We sought to evaluate the impact of chemotherapy sequence on survival by comparing node-positive invasive lobular carcinoma (ILC) patients who received neoadjuvant (NACT) and adjuvant (ACT) chemotherapy.

METHODS

cT1-4c, cN1-3 ILC patients in the National Cancer Data Base (2004-2013) who underwent surgery and chemotherapy were divided into NACT and ACT cohorts. Kaplan-Meier curves and Cox proportional hazards modeling were used to estimate unadjusted and adjusted overall survival (OS), respectively.

RESULTS

Five thousand five hundred fifty-one (35.6%) of 15 573 ILC patients treated with chemotherapy received NACT. NACT patients had similar rates of pT3/4 disease (26.6% vs 26.2%), nodal involvement (median 3 vs 4), and number of lymph nodes examined (median 13 vs 14) but higher rates of mastectomy (81.8% vs 74.5%, P < 0.001) vs ACT patients. 3.4% of NACT patients experienced pathologic complete response (pCR). Unadjusted 10-year OS was worse for NACT vs ACT patients (65.1% vs 54.4%, log-rank P < 0.001). After adjustment for known covariates, NACT continued to be associated with worse OS (hazard ratio [HR], 1.38; 95% confidence interval [CI], 1.25-1.52).

CONCLUSIONS

In node-positive ILC, NACT yielded low rates of pCR, was not associated with lower rates of mastectomy or less extensive axillary surgery, and was associated with worse survival vs ACT, suggesting limited benefit for these patients.

Evolution of the Use of Completion Axillary Lymph Node Dissection in Patients with T1/2N0M0 Breast Cancer and Tumour-Involved Sentinel Lymph Nodes Undergoing Mastectomy: A Cohort Study

BACKGROUND

In breast cancer, completion axillary lymph node dissection (cALND) was previously recommended for patients with at least one tumour-affected sentinel lymph node (SLN). Several prospective trials predominantly in patients undergoing breast-conserving surgery showed no benefit and increased arm morbidity with this procedure. We report the influence of these trials on clinical practice of patients undergoing mastectomy.

METHODS

We analysed prospectively collected data from patients with primary invasive breast cancer treated at German breast cancer units between January 2008 and December 2015. Time trends of cALND rates were analysed in patients undergoing mastectomy for T1/2N0M0 breast cancer with one or two tumour-involved SLNs. Multivariable logistic regression was used to determine factors influencing the decision not to perform cALND.

RESULTS

Among the entire study cohort of 166,074 patients treated at 179 breast cancer units, 4093 patients (2%) had T1/2N0M0 breast cancer with one or two tumour-involved SLNs and underwent mastectomy. cALND rates decreased from 89.9% in 2010 to 55.5% in 2015 (p < 0.001). Rates decreased from 82% to 8% in patients with micrometastatic SLN disease and from 93% to 63% in those with macrometastasis (p < 0.001). In multivariable analysis, factors associated with omission of cALND were treatment at a general, nonacademic hospital, pT1 status, older age, higher number of removed SLNs, fewer tumour-affected SLNs, and SLN micrometastasis (all p < 0.001).

CONCLUSIONS

Despite limited evidence from prospective trials relating to the omission of cALND specifically in patients undergoing mastectomy, our nationwide data show that use of cALND decreased in these patients in routine clinical practice.

Retrospectively validating the results of the ACOSOG Z0011 trial in a large Asian Z0011-eligible cohort

PURPOSE

The Z0011 trial demonstrated that axillary dissection (ALND) could be omitted during breast-conserving therapy for cT1-2N0 breast cancers with 1-2 metastatic SLNs. However, that result has not been validated in a larger cohort and the significance of the small number of SLNs remains unclear. This study aimed to validate the Z0011 results within an Asian Z0011-eligible cohort and determine whether the number of sentinel lymph nodes (SLNs) influenced the Z0011-based outcomes.

METHODS

Data from Asian patients who fulfilled the Z0011 criteria were collected from five hospitals. Disease recurrence (DR) was compared between patients who underwent ALND or SLN dissection (SLND) alone. Propensity-score matching was performed to reduce the effects of potential selection biases.

RESULTS

During 2010-2016, 1750 Asian patients had 1-2 SLN metastases and fulfilled the Z0011 criteria. These patients included 707 cases treated using SLND alone (40%) and 967 patients with ≤ 2 SLNs (55%). Ninety-five patients (5.4%) experienced DR at a median interval of 50 months, although the rates of DR were similar in the ALND and SLND groups. The adjusted hazard ratios for DR after ALND omission were 0.95 (95% CI 0.55-1.64) among the entire cohort and 0.83 (95% CI 0.34-2.03) among patients with ≤ 2 SLNs.

CONCLUSIONS

In this Asian Z0011-eligible cohort, ALND omission did not increase risk of DR, even among patients with ≤ 2 SLNs. Therefore, the Z0011 strategy might be safely applied in Asia, and a small number of SLNs did not significantly influence this strategy.

Reducing harms from treatment. Sixteen years of surgery of the axilla for screen-detected breast cancers in Italy

OBJECTIVES

Available evidence on axillary surgery has accumulated dramatically in the last two decades in favor of less invasive care. The aim of this paper is to study 16-years trends in the surgical management of the axilla in a large population-based data set of screen-detected breast cancers in Italy and to document at what extent recommendations have been adopted in actual clinical care.

MATERIAL AND METHODS

This is a retrospective cohort study documenting the surgical management of the axilla in primary breast cancer patients over time. We retrieved from the Italian database of screen-detected cancers 41213 cases diagnosed in women aged 50-69 between years 2000 and 2015 in twelve Italian Regions.

RESULTS

In pN0 cases, an increasing trend (p < 0.001) in the number of patients who received sentinel lymph node biopsy (SLNB) as the only axillary staging procedure was observed. In pN + cases SLNB was the only staging procedure in an increasing number of patients (p < 0.001) especially since the publication of the ACOSOG-Z0011 paper. In ductal carcinoma in situ (DCIS) SLNB was more frequent in mastectomies and in high grade and large lesions. However, 45% of low grade, small DCIS over the whole time period had some form of axillary surgery.

CONCLUSION

This large series of screen-detected cases documents a strong time trend in the direction of reducing axillary surgery and hence potential harms from treatment. The continuing practice of SLNB in low risk DCIS is of concern in an era of increasing awareness towards overdiagnosis and overtreatment.

The rationale for and long-term outcome of incomplete axillary staging in elderly women with primary breast cancer

BACKGROUND

The proportion of elderly women diagnosed with breast cancer is rising. Standard treatment, including axillary staging, is often not given to these patients. This study aimed to investigate reasons to omit any surgical axillary staging or to refrain from completion axillary lymph node dissection (cALND) after positive-sentinel lymph node biopsy (SLNB); so-called "incomplete staging". Furthermore, the impact of incomplete staging on regional control and survival in patients aged 75 or older was evaluated.

METHODS

A retrospective cohort study was conducted including all primary breast cancer patients aged 75 or older, diagnosed between 2001 and 2008, and documented by the Netherlands Cancer Registry (NCR). Patients with incomplete staging were compared to patients with complete axillary staging. Survival analyses were used to determine the risk of local, regional and distant recurrence and overall survival.

RESULTS

In total, 1467 of 2116 (69%) patients were considered eligible, of whom 258 (17.2%) had incomplete axillary staging. For 93 patients, diagnosed in 6 of the 10 hospitals in the NCR-area, examination of clinical records revealed that age, comorbidities and patient preferences were the main reason for omitting complete axillary staging. The 10-year axillary recurrence rate in these 93 patients was 5.2% (95% CI, 0.03-10.1). Of the 77 patients who had died, 64 (83%) died of non-breast-cancer-related causes. No significant difference in overall survival was observed between patients with or without complete axillary staging.

CONCLUSION

This study demonstrates that the omission of complete axillary staging is common in selected elderly breast cancer patients with ≥2 comorbidities, with no apparent impact on regional control and 10-year overall survival.