Oncologic outcomes in breast cancer patients with metastatic nodes and pathological nodal response following neoadjuvant chemotherapy without axillary dissection: a literature review

BACKGROUND AND OBJECTIVE: With promising nodal pathological complete response (pCR) after neoadjuvant chemotherapy, the role of axillary lymph node dissection (ALND) was questioned. While there is much data on the accuracy of axillary staging after neoadjuvant chemotherapy to predict nodal pCR, limited data on the oncological safety of omitting ALND exists. We aim to review the oncological safety of omitting ALND in patients with initially metastatic nodes achieving nodal pCR, based on axillary staging, following neoadjuvant chemotherapy. METHODS: A PubMed search of relevant articles from 1(st) January 2013 to 15(th) September 2022 was performed. Studies with duplication of patients, ALND only, no oncological details, initially N0 patients only and patients without nodal pCR were excluded. KEY CONTENT AND FINDINGS: Fifteen studies with 1,515 eligible patients (range, 29–242 patients) were analysed. There was heterogeneity of patients among the included studies and patients had varying TN staging, making selection criteria for omission of ALND inconclusive. Sentinel lymph node biopsy (SLNB) was the most studied mode of axillary staging in 1,416 (93.5%) patients, though 35.7% had <3 SLN harvested. On average median follow-up of 52.8 months (range, 9–110 months), axillary recurrence ranged from 0% to 3.4%. There was limited data on survival outcomes. CONCLUSIONS: In node positive breast cancer patients who achieved nodal pCR after neoadjuvant chemotherapy, the axillary recurrence rate was low without ALND. However, survival data was limited. The selection criteria and ideal axillary staging technique for patients, who are suitable for axillary preservation, are unclear. More prospective studies with longer follow-up, providing survival data, are needed.