Long-Term Survival Outcomes and Risk Factors for Axillary and Locoregional Recurrence in Japanese Patients with Sentinel Node-Positive Breast Cancer Treated in Accordance with the ACOSOG Z0011 Strategy

INTRODUCTION

In 2018, we reported the results of a study to assess the feasibility of applying the ACOSOG Z0011 criteria to Japanese patients with early-stage breast cancer (median follow-up, 3 years). Their results over the longer term can now be presented. Risk factors for axillary and locoregional recurrence in Z0011-eligible patients are unknown.

METHODS

Long-term survival outcomes were investigated by analyzing data from patients enrolled in the feasibility study. Data from the feasibility study patients, and from patients eligible for the Z0011 strategy after its introduction into clinical practice, were subjected to multivariate logistic regression analysis to identify risk factors for axillary and locoregional recurrence.

RESULTS

Regarding long-term outcomes for the feasibility study patients (n = 189), distant disease-free survival rates at 5 and 7 years were 90.4 ± 2.1% and 85.9 ± 2.6%, respectively, and overall survival rates at 5 and 7 years were 97.3 ± 1.2% and 95.3 ± 1.7%, respectively. Analysis of data from these patients plus the 93 who received Z0011 in clinical practice (total, n = 282) identified the following independent risk factors for axillary recurrence: absence of high axillary tangential irradiation (OR, 5.87 [95% CI, 1.09-31.35], p = 0.04) and number of positive sentinel lymph nodes (OR, 4.65 [95% CI, 1.11-19.48], p = 0.04). Only high Ki67 labeling index (OR, 5.92 [95% CI, 1.31-26.70], p = 0.02) was identified as an independent risk factor for locoregional recurrence.

CONCLUSION

Long-term survival outcome results of the feasibility study show that the Z0011 strategy can be used to treat Japanese patients with early-stage breast cancer. Our findings regarding risk factors suggest that high axillary tangent irradiation is necessary for the prevention of axillary recurrence and that irradiation, including of the regional lymph nodes, should be considered, especially in patients with high Ki67 index values.

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.

Preservation of Axillary Lymph Nodes Compared with Complete Dissection in T1-2 Breast Cancer Patients Presenting One or Two Metastatic Sentinel Lymph Nodes: The SINODAR-ONE Multicenter Randomized Clinical Trial

BACKGROUND

The SINODAR-ONE trial is a prospective noninferiority multicenter randomized study aimed at assessing the role of axillary lymph node dissection (ALND) in patients undergoing either breast-conserving surgery or mastectomy for T1-2 breast cancer (BC) and presenting one or two macrometastatic sentinel lymph nodes (SLNs). The endpoints were to evaluate whether SLN biopsy (SLNB) only was associated with worsening of the prognosis compared with ALND in terms of overall survival (OS) and relapse.

METHODS

Patients were randomly assigned (1:1 ratio) to either removal of ≥ 10 axillary level I/II non-SLNs followed by adjuvant therapy (standard arm) or no further axillary treatment (experimental arm).

RESULTS

The trial started in April 2015 and ceased in April 2020, involving 889 patients. Median follow-up was 34.0 months. There were eight deaths (ALND, 4; SNLB only, 4), with 5-year cumulative mortality of 5.8% and 2.1% in the standard and experimental arm, respectively (p = 0.984). There were 26 recurrences (ALND 11; SNLB only, 15), with 5-year cumulative incidence of recurrence of 6.9% and 3.3% in the standard and experimental arm, respectively (p = 0.444). Only one axillary lymph node recurrence was observed in each arm. The 5-year OS rates were 98.9% and 98.8%, in the ALND and SNLB-only arm, respectively (p = 0.936).

CONCLUSIONS

The 3-year survival and relapse rates of T1-2 BC patients with one or two macrometastatic SLNs treated with SLNB only, and adjuvant therapy, were not inferior to those of patients treated with ALND. These results do not support the use of routine ALND.

Axillary Clearance Following Positive Sentinel Lymph Node Biopsy in Symptomatic Breast Cancer

BACKGROUND/AIM

Symptomatic cancers display a different biological behaviour from screen-detected cancers, which may impact the management of axillary metastases. We aimed to determine the role of unselected axillary nodal clearance (ANC) in symptomatic patients with positive sentinel node biopsies (SNBs).

PATIENTS AND METHODS

A case-note review was performed on 95 symptomatic breast cancer patients who underwent ANC following positive SNB.

RESULTS

Thirty-eight (40%) patients were treated with a mastectomy and 57 (60%) with breast-conserving surgery. At ANC, 25 patients (26.3%) showed evidence of further lymph node metastases, with 15 (60%) having two or fewer macrometastases. The presence of more than 2 SNB macrometastases was associated with further ANC metastases (p<0.001). The presence of further metastases at ANC was not associated with either reduced overall survival or disease-free survival.

CONCLUSION

A number of symptomatic breast cancer patients with positive SNBs may be overtreated. Ongoing trials examining the management of low volume SNB macrometastases need to consider the symptomatic subgroup in their conclusions.

Omitting ALND Is Not Safe for a Cohort of Early-Stage Breast Cancer Patients with 1-2 SLNs Macro-Metastases and Breast-Conserving Therapy: A Single-Center Retrospective Study

Background:

Omitting axillary lymph node dissection (ALND) is recommended for early-stage breast cancer patients with 1–2 sentinel lymph nodes (SLNs) macro-metastases and breast-conserving therapy. However, it is not safe for part of patients, so it is significant to find risk factors and develop a predictive model of non-SLNs metastases in breast cancer patients with 1–2 SLNs macro-metastases and breast-conserving therapy.

Methods:

This retrospective study enrolled 228 breast cancer patients with 1–2 SLNs macro-metastases who underwent ALND and breast-conserving surgery between Jan 2012 and Dec 2017 at Cancer Hospital Chinese Academy of Medical Sciences. Chi-square test and backward stepwise binary logistic regression were used to find factors that influenced non-SLN metastases, then a predictive model was formulated and obtained its area under the curve.

Results:

Tumor pathologic invasion size, number of positive SLNs and ALN status on imaging was associated with non-SLNs metastases. The predictive model was also formulated based on these three factors to assess and the area under the curve of model was 0.708.

Conclusion:

We developed a predictive model to assess the high-risk cohort of patients of non-SLNs metastases which can be an auxiliary tool for doctors.

External Validation of the SERC Trial Population: Comparison with the Multicenter French Cohort, the Swedish and SENOMIC Trial Populations for Breast Cancer Patients with Sentinel Node Micro-Metastasis

Simple Summary

After the results of many trials, it is now accepted to omit axillary dissection in selected patients with limited axillary involvement. However, the external validity of these trials is questionable. Our study aimed to evaluate the accuracy of the real French population representativity in the SERC (Sentinelle Envahi et Randomisation du Curage) trial population for patients with breast cancer (BC) associated with sentinel node (SN) micro-metastasis and the differences between the studied population and the real French population. The secondary aim was to compare the French and the Swedish populations of patients with SN micro-metastasis. The findings of our study in addition to the previously demonstrated concordance between the SENOMIC (Sentinelle node Micrometastasis) trial and the Swedish National Breast Cancer Registry (NKBC) populations implied that the results of both the SERC and the SENOMIC trials can be applied to both the French and Swedish real populations.

Abstract

Many trials confirmed the safety of omitting axillary dissection in the selected patients treated for early breast cancer. The external validity of these trials is questionable. Our study aimed to evaluate the accuracy of the French population representativity in the SERC trial and the differences between these two populations as well as comparing the French and the Swedish populations (the SENOMIC trial population and the Swedish National Breast Cancer Registry (NKBC) cohort) of patients with sentinel node (SN) micro-metastasis. A higher rate of smaller tumors and grade 1 tumors was observed in the French cohort when compared to the SERC population. Our findings conclude that both French populations show similar characteristics. Positive non-sentinel node (NSN) rates at completion axillary lymph node dissection (ALND) were 10.28 % and 11.3 % in the SERC trial and French cohort, respectively (p = 0.5). The rate of grade 1 tumors was lower in the SENOMIC trial (16.2%) and in the NKBC cohort (17.4%) compared to the SERC trial population (27.3%) and the French cohort (34.4%). Our findings in addition to the previously demonstrated concordance between the SENOMIC trial and the NKBC populations imply that the results of both the SERC and the SENOMIC trials can be applied to both French and Swedish real populations.

Predictive factors of lymph node metastasis and effectiveness of intraoperative examination of sentinel lymph node in breast carcinoma: A retrospective Belgian study

Recently, several trials demonstrated the safety of omitting axillary lymph node dissection in clinically N0 patients with positive sentinel nodes in select subgroups. However, this fact is still troublesome to clarify to surgeons and clinicians, as they used to perform intraoperative examination of the sentinel node and axillary dissection for many years. Hence, we decided to review our practice. This is to firstly highlight the predictive factors of node metastasis and secondly, to evaluate the effectiveness of intraoperative examination of the sentinel node. There were 406 total procedures. The rate of positive lymph nodes in the final diagnosis was 27%. Factors associated with metastasis were age, tumour size, TNM classification, tumour grade, vascular invasion, molecular classification and KI-67 index. The rate of reoperation was 6.2% in cases with final positive nodes, however, the complementary ALND was justified in only 2.7%. Forty-nine percent of SLN were examined during surgery (IOESLN), whereby the false negative rate was 11.8%. Sixty-three intraoperative examinations were necessary to prevent a second operation on a patient. We recommend changing the clinical management of the axilla, resulting in fewer ALNDs in selected cN0, SLN-positive patients. In keeping with recent large clinical trial (ACOSOG Z0011, AMAROS and OTOASOR) data, our results support that intraoperative exam in selected cN0, SLN-positive Belgian patients is no longer effective.

Axillary dissection in sentinel lymph node positive breast cancer: Is the staging information worthwhile for patients?

AIMS

The Z0011 randomized trial demonstrated no significant difference in axillary recurrence rate or survival with or without axillary dissection in patients with a positive sentinel node biopsy. However, there is continuing controversy regarding the generalizability of its results, and axillary dissection provides additional pathologic staging information that may guide adjuvant therapy. Thus, axillary dissection after positive sentinel node biopsy is being further investigated in an actively recruiting randomized trial. We elicited patients' preferences for axillary dissection versus no axillary dissection after positive sentinel node biopsy for early breast cancer.

METHODS

Patients who had undergone axillary dissection after positive sentinel node biopsy as part of breast conserving therapy were provided with a validated, self-rated questionnaire. The questionnaire comprised two trade-off questions to determine the maximum chance of developing arm side-effects from axillary dissection to justify the benefit of additional axillary staging information. Social, demographic, and clinical details were collected.

RESULTS

Ninety-nine of the 126 eligible patients returned the questionnaire and 76 completed the trade-off assessment. The median age of participants was 62 years. The median numbers of sentinel and axillary nodes removed were 2 and 12, respectively. Forty-seven percent of participants had arm swelling or tenderness of any severity. Seventy-five percent of participants would have axillary dissection even if the chance of arm side-effects like they had experienced was 100%.

CONCLUSION

Most patients with early breast cancer preferred axillary dissection after positive sentinel node biopsy for the additional staging information even though there was no survival benefit from axillary dissection.

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).

Trends in axillary lymph node dissection for early-stage breast cancer in Europe: Impact of evidence on practice

BACKGROUND

Data from recently published trials have provided practice-changing recommendations for the surgical approach to the axilla in breast cancer. Patients with T1-2 lesions, treated with breast conservation, who have not received neoadjuvant chemotherapy and have 1-2 positive sentinel nodes (Z0011-criteria) may avoid axillary lymph node dissection (ALND). We aim to describe the dissemination of this practice in Europe over an extended period of time.

METHODS

Our source of data was the eusomaDB, a central data warehouse of prospectively collected information of the European Society of Breast Cancer Specialists (EUSOMA). We identified cases fulfilling Z0011-criteria from 2005 to 2016 from 34 European breast centers and report trends in ALND. Data derived from Germany, Italy, Belgium, Switzerland, Austria, and Netherlands.

RESULTS

6671 patients fulfilled Z0011-criteria. Rates of ALND showed a statistically significant decrease from 2010 (89%) to 2011 (73%), reaching 46% in 2016 (p < 0.001). After multivariable analysis, factors associated with higher probability of ALND were earlier year of surgery, younger age, increasing tumor size and grade, and being operated in Italy (p < 0.001). The minimum and maximal rates of ALND in the most recent two-year period (2015-2016) were 0% and 83% in two centers located in different countries (p < 0.001).

CONCLUSION

Our study demonstrates, a decrease in rates of ALND that started after year 2010 through the end of the study period. Wide differences were observed among centers and countries indicating the need to spread unified clinical guidelines in Europe to allow for homogeneous evidence-based practice patterns.

Elaboration of a nomogram to predict nonsentinel node status in breast cancer patients with positive sentinel node, intraoperatively assessed with one step nucleic amplification: Retrospective and validation phase

BACKGROUND

Tumor-positive sentinel lymph node (SLN) biopsy results in a risk of non sentinel node metastases in micro- and macro-metastases ranging from 20 to 50%, respectively. Therefore, most patients underwent unnecessary axillary lymph node dissections. We have previously developed a mathematical model for predicting patient-specific risk of non sentinel node (NSN) metastases based on 2460 patients. The study reports the results of the validation phase where a total of 1945 patients were enrolled, aimed at identifying a tool that gives the possibility to the surgeon to choose intraoperatively whether to perform or not axillary lymph node dissection (ALND).

METHODS

The following parameters were recorded: Clinical: hospital, age, medical record number; Bio pathological: Tumor (T) size stratified in quartiles, grading (G), histologic type, lymphatic/vascular invasion (LVI), ER-PR status, Ki 67, molecular classification (Luminal A, Luminal B, HER-2 Like, Triple negative); Sentinel and non-sentinel node related: Number of NSNs removed, number of positive NSNs, cytokeratin 19 (CK19) mRNA copy number of positive sentinel nodes stratified in quartiles. A total of 1945 patients were included in the database. All patient data were provided by the authors of this paper.

RESULTS

The discrimination of the model quantified with the area under the receiver operating characteristics (ROC) curve (AUC), was 0.65 and 0.71 in the validation and retrospective phase, respectively. The calibration determines the distance between predicted outcome and actual outcome. The mean difference between predicted/observed was 2.3 and 6.3% in the retrospective and in the validation phase, respectively. The two values are quite similar and as a result we can conclude that the nomogram effectiveness was validated. Moreover, the ROC curve identified in the risk category of 31% of positive NSNs, the best compromise between false negative and positive rates i.e. when ALND is unnecessary (<31%) or recommended (>31%).

CONCLUSIONS

The results of the study confirm that OSNA nomogram may help surgeons make an intraoperative decision on whether to perform ALND or not in case of positive sentinel nodes, and the patient to accept this decision based on a reliable estimation on the true percentage of NSN involvement. The use of this nomogram achieves two main gools: 1) the choice of the right treatment during the operation, 2) to avoid for the patient a second surgery procedure.

A Population-Based Study of the Effects of a Regional Guideline for Completion Axillary Lymph Node Dissection on Axillary Surgery in Patients with Breast Cancer

INTRODUCTION

Evidence from the American College of Surgeons Oncology Group (ACOSOG) Z0011 trial suggests completion axillary lymph node dissection (cALND) after positive sentinel lymph node biopsy (+SLNB) does not improve outcomes in select patients, leading to practice variation. A multidisciplinary group of surgeons, oncologists, and pathologists developed a regional guideline for cALND which was disseminated in August 2012. We assessed the impact of Z0011 and the regional guideline on cALND rates.

METHODS

Consecutive invasive breast cancer cases undergoing SLNB were reviewed at 12 hospitals. Patient, tumor, and process measures were collected for three time periods: TP1, before publication of Z0011 (May 2009-August 2010); TP2, after publication of Z0011 (March 2011-June 2012); and TP3, after guideline dissemination (January 2013-April 2014). Cases were categorized by whether they met the guideline criteria for cALND (i.e. ≤50 years, mastectomy, T3 tumor, three or more positive sentinel lymph nodes [SLNs]) or not (e.g. age > 50 years, breast-conserving surgery, T1/T2 tumor, and one to two positive SLNs).

RESULTS

The SLNB rate increased from 56 % (n = 620), to 70 % (n = 774), to 78 % (n = 844) in TP1, TP2, and TP3, respectively. Among cases not recommended for cALND using the guideline criteria, cALND rates decreased significantly over time (TP1, 71 %; TP2, 43 %; TP3, 17 %) [p < 0.001]. The cALND rate also decreased over time among cases recommended to have cALND using the guideline criteria (TP1, 92 %; TP2, 69 %; TP3, 58 %) [p < 0.001]. Based on multivariable analysis, age and nodal factors appeared to be significant factors for cALND decision making.

CONCLUSION

Publication of ACOSOG Z0011 and regional guideline dissemination were associated with a marked decrease in cALND after +SLNB, even among several cases in which the guideline recommended cALND.

Practice Patterns of Radiation Field Design for Sentinel Lymph Node-Positive Early-Stage Breast Cancer

BACKGROUND

Recent randomized trials have led to decreased use of completion axillary lymph node dissection (ALND) in early-stage breast cancer patients with a positive sentinel lymph node (SLN), causing controversy surrounding radiotherapy coverage of the axilla. We investigated the practice variation among radiation oncologists for regional nodal coverage for clinicopathologic scenarios and evaluated axillary field design decision-making processes.

MATERIALS AND METHODS

A customized, web-based questionnaire was e-mailed to 983 community (n = 617) and academic (n = 366) radiation oncologists with a breast cancer subspecialty practicing in the United States. The survey consisted of 18 multiple-choice questions evaluating general clinical preferences surrounding radiation therapy (RT) field design for patients with early-stage breast cancer and a positive SLN. Seven case scenarios were developed to investigate the field design in the setting of specific clinical and pathologic risk factors. Nodal coverage was classified as standard tangents (STs), high tangents (HTs), STs and a supraclavicular field (SCF), or STs and full axillary coverage (AX).

RESULTS

A total of 145 evaluable responses were collected, with a response rate of 15.0%. Of the respondents, 12 (8.3%) reported using completion ALND for patients with 1 to 3 positive SLNs without extracapsular extension (ECE) and 66 (45.5%) performed ALND with 1 to 3 positive SLNs with ECE. For micrometastatic SLNs, with no lymphovascular system invasion, 115 (87.1%) used STs or HTs. The use of neoadjuvant chemotherapy (NAC) influenced RT field design for patients with a positive SLN without ECE, with 64 (48.5%) using STs and SCF or STs and AX treatment without NAC and 94 (70.7%) using SCF and AX after NAC. With macrometastatic SLN involvement, most respondents preferred SCF (45.27%) and AX (45.66%). In contrast, for micrometastatic involvement, HTs (43.61%) were frequently chosen. Forty (27.8%) reported using online predictive nomograms to predict further axillary involvement, with no difference between the academic and community radiation oncologists (P = .11).

CONCLUSION

In SLN biopsy-positive early-stage breast cancer with omission of completion ALND, axillary RT is increasing used to cover the undissected axilla. Most respondents use SCF or AX for patients with low to intermediate pathologic features. Online prediction nomograms are used by a few practitioners to assist in clinical decision-making in this setting.

Sentinel lymph nodes for breast carcinoma: an update on current practice

Sentinel lymph node (SLN) biopsy has been established as the standard of care for axillary staging in patients with invasive breast carcinoma and clinically negative lymph nodes (cN0). Historically, all patients with a positive SLN underwent axillary lymph node dissection (ALND). The ACOSOG Z0011 trial showed that women with T1-T2 disease and cN0 who undergo breast-conserving surgery and whole-breast radiotherapy can safely avoid ALND. The main goal of SLN examination should be to detect all macrometastases (>2 mm). Gross sectioning of SLNs at 2-mm intervals and microscopic examination of one haematoxylin and eosin-stained section from each SLN block is the preferred method for pathological evaluation of SLNs. The role and timing of SLN biopsy for patients who have received neoadjuvant chemotherapy is controversial, and continues to be explored in clinical trials. SLN biopsies from patients with invasive breast carcinoma who have received neoadjuvant chemotherapy pose particular challenges for pathologists.