Patterns of axillary staging and management in clinically node positive breast cancer patients treated with neoadjuvant systemic therapy: Results of a survey amongst breast cancer specialists

Abstract

Introduction

Various options for axillary staging after neoadjuvant systemic therapy (NST) are available for breast cancer patients with a clinically positive axillary node (cN+). This survey assessed current practices amongst breast cancer specialists.

Materials and methods

A survey was performed amongst members of the European Society of Surgical Oncology and two UK-based Associations: the Association of Breast Surgery and the British Association of Surgical Oncology. The survey included 3 parts: 1. general information, 2. diagnostic work-up and 3. axillary staging after NST.

Results

A total of 310 responses were collected: parts 1, 2 and 3 were fully completed by 282 (91%), 270 (87.1%) and 225 (72.6%) respondents respectively. After NST, 153/267 (57.3%) respondents currently perform ALND routinely and 114 (42.7%) respondents perform less invasive restaging of the axilla with possible omission of ALND. In the latter group, 85% does and 15% does not use nodal response seen on imaging to guide the axillary restaging procedure. Regarding respondents that do use imaging: 95% would perform a less invasive staging procedure in case of complete nodal response on imaging (63% sentinel lymph node biopsy (SLNB), excision of a previously marked positive node with SLNB (21%) and without SLNB (11%)). In case of no nodal response on imaging 77% would perform ALND.

Conclusion

Current axillary staging and management practices in cN + patients after NST vary widely. To determine optimal axillary staging and management in terms of quality of life and oncologic safety, breast specialists are encouraged to include patients in clinical trials/prospective registries.

Introduction

The management of the axilla in clinically node-negative breast cancer patients has evolved towards a less or even non-invasive approach. For clinically node-positive breast cancer patients (cN+) however, the axillary lymph node dissection (ALND) has been the standard of care until recently. cN + patients are increasingly receiving systemic therapy before surgery (i.e. neoadjuvant systemic therapy (NST)). As a result of NST, in at least 1/3 of pre-treatment cN + patients the axilla converts to node-negative [1]. In case of a pathologic complete response (pCR) in the axilla, ALND may be unnecessary and its purpose is therefore being questioned [2,3].

In order to identify cN + ypN0 patients, several less invasive procedures have been proposed. These procedures can be largely divided into 3 groups: sentinel lymph node biopsy (SLNB), excision of a pre-treatment marked positive lymph node (e.g. MARI: Marking Axillary lymph node with Radioactive Iodine seed) [4] or procedures involving the combination of both (e.g. TAD: Targeted Axillary Dissection [5], RISAS: Radioactive Iodine Seed localization in the Axilla combined with a SLNB; the iodine seed is placed in the positive axillary lymph node prior to start of NST [6]). Currently, no consensus exists on which procedure is most accurate for axillary staging after NST. Moreover, long-term data on whether these less invasive procedures can safely replace ALND, even in case of axillary pCR, are lacking.

The lack of evidence based consensus guidelines for cN + patients treated with NST results into broadly differing patterns of care in the management of the axilla. The present survey focused on breast cancer specialists (mainly European) to assess current practices regarding diagnostic work up and axillary staging in cN + patients treated with NST.