Overexploring and overtreating the axilla

Ongoing clinical trials on axillary management

INTRODUCTION

Within the last 50 years the management of patients with breast cancer has changed dramatically with a significant de-escalation of the role and magnitude of surgery, both for the management of the primary tumor and for the management of the axilla. In the management of the axilla of patients with early stage breast cancer (EBC) and clinically uninvolved axilla (cN0), axillary lymph node dissection (ALND) was gradually replaced by sentinel lymph node biopsy (SLNB) saving more than 60-70% of patients from an unnecessary dissection. Further studies confirmed that isolated tumor cells or micrometastases found on the SLN had no further benefit from ALND sparing even more patients from an unnecessary ALND. Eventually, the Z0011 and other studies showed that even patients with 1-2 positive SLN can be spared from ALND provided they fulfill certain criteria. Still though there were many flaws in these studies and further research was necessary to generalize the results of these studies to a wider target group. Meanwhile, there is a clear view that many low risk patients if they have their axilla evaluated via US and are not found to have suspicious nodes, it is highly unlikely to have involved axilla. This let to studies evaluating the non-surgical management of the axilla. Finally, in the post neoadjuvant setting 3 randomized controlled trials showed that under certain circumstances SLNB can be done after the NAC even in patients who initially had involved axilla and was converted to clinically uninvolved (cN1→cN0).

EVIDENCE ACQUISITION

PubMed, Medline, the Cochrane Library Controlled Trials Register as well as National Institutes of Health ClinicalTrials.Gov database have been consulted up to May 2020.

EVIDENCE SYNTHESIS

We studied and described the ongoing trials on patients not undergoing neoadjuvant chemotherapy and we discussed the eligibility criteria, the comparison arms and the expected outcomes. We further examined the ongoing trials on patients undergoing neoadjuvant chemotherapy in the same manner.

CONCLUSIONS

Although we have covered a long way in the journey of eliminating axillary surgery, there are still lots of questions to be answered and trials to be conducted. We anticipate the results of the ongoing trials to provide the necessary evidence to safely de-escalate more the axillary surgery, both in the non-neoadjuvant as well as in the neoadjuvant setting, hoping that in the not so far future the axillary surgery will eventually perish.

The value of the intraoperative assessment of the SLN via frozen section in the post Z0011 era

INTRODUCTION

Sentinel node (SN) assessment via frozen section (FS) has declined since the publication of Z0011 which modified the management of a specific group of patients with positive SN. The risk of misleading the surgeons to a preventable ALND and the cost are among the main factors for that. The aim of our study is to assess the value of FS in the post Z0011.

MATERIAL AND METHODS

244 patients out of 434 were eligible for an upfront SLNB. Based on the final histology and the clinical data we selected the eligible for breast conserving surgery patients (55.4%). 78 patients had positive SN and 26 of them fulfilled the criteria of Z0011. We assessed the false negative findings, the impact on the management and the indications and value of FS in the post Z0011 era.

RESULTS

Overall, there were 12 FN cases out of which 7 were macrometastases (8.97%). Only in one case there were > 2 positive LN and 3 patients needed mastectomy. The remaining cases fulfilled the criteria of Z0011 and needed no further surgery hence in 96.1% of the cases the axillary status was correctly assessed via FS and the reoperation rate was 1.2%. On the contrary, if FS was not used, at least 21.3% of the patents would have needed reoperation based on the today's guidelines.

DISCUSSION

We believe FS is still valuable and may spare a significant percentage of patients from a second operation (SNB) without leading to axillary overtreatment if used wisely.

L’exploration axillaire : un standard du bilan préthérapeutique

L’exploration préthérapeutique axillaire est une étape majeure du bilan initial du cancer du sein. L’échographie associée à un prélèvement est actuellement recommandée en première intention. L’IRM et la TEP/TDM au 18FDG sont utiles dans l’évaluation ganglionnaire axillaire. Les sensibilités et spécificités des examens d’imagerie sont globalement identiques, et leur combinaison permet d’obtenir les meilleures performances. Actuellement, la technique du ganglion sentinelle est indispensable en cas de tumeurs mammaires T1-T2 N0 et en cas d’adénopathie suspecte échographiquement avec cytoponction ou microbiopsie négative.

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 predictive value of sentinel node biopsy in early breast cancer after neo-adjuvant chemotherapy: A prospective study

OBJECTIVE

A sentinel Node (SN) has replaced axillary lymph node dissection (ALND) in patients with clinically node negative axilla (cN0). SN after Neo-adjuvant chemotherapy (NACT) is feasible but not accurate in clinically node positive (cN1-3) patients. The goal of this study is to determine the negative predictive value (NPV) of SN in cN0 breast cancer after NACT. A secondary endpoint is to determine if ALND can be avoided after NACT regardless of the pre-treatment clinical staging of the axilla, in case of a normalization of the ¹⁸F-fluoro-2-deoxy-glucose positron emission tomography scan (PET-CT scan).

DESIGN

A single institution prospective study regarding the negative predictive value of the SN in breast cancer after NACT was conducted in the Multidisciplinary Breast Clinic of the Antwerp University Hospital from 29/03/2010 until 01/12/2015 (Study number: B30020108368). Inclusion criteria for study participation were: breast cancer, age above 18 years, female, tumor stages T2-T4 N0-3 or T1N1-N3. All patients were staged by a mammography, ultrasound of the axilla, MRI of the breast, PET-CT scan and bone scintigraphy. They received NACT consisting of 12 cycles of paclitaxel or 4 cycles of docetaxel followed by dose dense doxorubicin or epirubicin/cyclofosfamide or vice versa as a standard initial treatment. After 6 weeks, a PET-CT scan was performed for early tumour response evaluation. At the day of operation, a ⁹⁹mTC-labelled nanocolloid was used to identify the SN. During the surgery the SN were removed separately together with a complete ALND.

RESULTS

A total of 150 patients were enrolled in our study of which 129 were eligible for analysis. 53 patients had a positive SN of which 32 have a positive axillary lymph nodes (ALN), positive predictive value (PPV) was 60%; 76 patients had a negative SN of which 6 had a positive ALN (NPV 92%). The sensitivity is 84% and the specificity 76% with a false omission rate (FOR) of 8%. In total 45 patients ALN were clinical negative and no suspect lymph nodes were seen on ultrasound, MRI and PET-CT scan) and 45 patients had negative a SN, with no ALN and 2 patients had a positive SN of which 1 patients had axillary involvement (NPV 100%). The FOR of cN1: 5%, cN2: 37%, cN3 33%. A total of 22 patients out of 84 patients (26%) of which 15/49 cN1 (30%), 6/23 (26%) cN2, 1/12 (8%) have after 6 weeks of chemotherapy and normalization on PET-CT scan. A total of 17 patients had a negative SN and ALN. The FOR was in this group was 0%.

CONCLUSION

A SNB should become the standard after NACT if case of a cN0. If after NACT the PET CT has normalized, no ALND should be performed if the SN is negative.

Prognostic value of isolated tumour cells in sentinel lymph nodes in early-stage breast cancer: a prospective study

BACKGROUND

The prognostic significance of isolated tumour cells (ITCs) in the sentinel nodes (SNs) is controversial in early breast cancer, and some centres have abandoned immunohistochemistry to detect ITCs.

METHODS

Patients with unilateral pT1N0 breast cancer, operated between February 2001 and August 2005 at a university hospital were included in this prospective, population-based cohort study. Survival of 936 patients with or without isolated tumour cells (ITC) in their SNs were compared with the log-rank test and Cox regression analysis.

RESULTS

Eight hundred sixty one (92.0%) patients were ITC-negative (pN0i-) and 75 (8.0%) ITC-positive (pN0i+). Patients with ITC-positive cancer received more frequently adjuvant systemic therapies than those with ITC-negative cancer. The median follow-up time was 9.5 years. Ten-year distant disease-free survival was 95.3% in the pN0i- group and 88.8% in the pN0i+ group (P = 0.013). ITCs were an independent prognostic factor in a Cox regression model (HR = 2.34, 95% CI 1.09-5.04; P = 0.029), together with tumour Ki-67 proliferation index and diameter. ITCs were associated with unfavourable overall survival (P = 0.005) and breast cancer-specific survival (P = 0.001).

CONCLUSIONS

We conclude that presence of ITCs in the SNs is an adverse prognostic factor in early small node-negative breast cancer, and may be considered in the decision-making for adjuvant therapy.