Surgical Management of Axilla Following Neoadjuvant Endocrine Therapy

Abstract

Background. Randomized clinical trials support deescalation of axillary surgery in breast cancer patients with lowvolume axillary disease treated with a surgery-first approach. However, few data exist to guide axillary surgery following neoadjuvant endocrine therapy (NET). Therefore, we evaluated the extent and outcomes of axillary surgery in a contemporary cohort of NET patients, a treatment approach that has become particularly relevant during the coronavirus disease-19 (COVID-19) pandemic. Patients and Methods. We identified invasive breast cancer patients treated with NET between October 2008 and November 2019. Patients presenting with stage IV disease or recurrent disease were excluded. Statistical analyses were performed using chi-square, Fisher's exact, and Wilcoxon rank-sum tests. Results. 194 invasive breast cancers in 186 patients (median age 66 years) were evaluated; 81 patients had breastconserving surgery (BCS), while 113 underwent mastectomy. Eighty-four patients (43.3%) were biopsy-proven cN? with 4/84 (4.8%) ypN0 following NET. Among cN? patients, 14 (16.7%) had sentinel lymph node biopsy (SLNB) only, 27 (32.1%) had SLNB ? axillary lymph node dissection (ALND), and 43 (51.2%) had ALND. Among 110 cN0 patients, 99 had axillary surgery with 28/99 (28.3%) ypN?: SLNB in 83 (75.5%), SLNB?ALND in 14 (12.7%), and ALND in 2 (1.8%). Among all ypN? patients, 23/108 (21.3%) had SLNB alone: 18/43 (41.9%) of BCS and 5/65 (7.7%) mastectomy patients (p\0.001). After median follow-up of 35 months, no regional recurrences were observed. Conclusions. Among biopsy-proven cN? NET patients, we observed deescalation of axillary surgery in selected patients, despite a low nodal pathologic complete response (pCR) rate, without nodal recurrences. These data suggest that patients with low-volume axillary disease treated with NET may be managed similarly to patients treated with a surgery-first approach.

Radiological, pathological and surgical outcomes after neoadjuvant endocrine treatment in patients with ER-positive/HER2-negative breast cancer with a clinical high risk and a low-risk 70-gene signature

“…The pathological response of the axilla (20%) was higher compared to pathological response rate of the breast. This aligns with previous studies, reporting a nodal pathological response after NET ranging from 4.8% to 13% [ [31] , [32] , [33] ]. Given our relative small sample size these results should be interpreted with caution.…”

“…A review conducted by Weiss et al demonstrated that in 10–50% of the patient remaining node-positive after NET, no ALND was performed [ 40 ]. One of these studies reported 17% of the clinical N1 patients undergoing only sentinel node biopsy, with no regional recurrences reported after a median follow up of 35 months [ 32 ]. In our study, none of the patients who remained node-positive underwent an ALND, instead they were all treated with radiotherapy.…”

Breast Cancer Management in the Era of Covid-19; Key Issues, Contemporary Strategies, and Future Implications

“… 66 Similarly, Murphy et al reported successful selective de-escalation of axillary surgery in breast cancer patients treated with NET. 80 …”

“… The patients were satisfied with telemedicine. Murphy et al, USA 80 Observational study 2008–2019 186 (66 years) Surgical management of axilla following NET Selective de-escalation of axillary surgery was done effectively in breast cancer patients treated with NET in the same way as the current way of treating first with surgery. Breast cancer patients receiving NET can be managed safely by adopting the same way as patients with similar tumours treated with a surgery-first approach.…”

ASO Author Reflections: Right Sizing Axillary Surgery in Patients treated with Neoadjuvant Endocrine Therapy

“…This occurred for patients with who presented with both clinically nodenegative and clinically node-positive disease and who were found to have limited axillary nodal disease (1 to 2 positive nodes) at surgery after NET. 4 Across both groups, omittance of axillary dissection or axillary radiation or both was not associated with axillary nodal relapse. This indicates that thoughtful extrapolation to the NET setting of reduced axillary treatment is appropriate.…”