Limited Axillary Dissection for Substantial Breast Cancer Axillary Tumor Burden

The axillary surgical management in breast cancer is de-escalating but level 1 + 2 axillary lymph node dissection (ALND) remains the standard of care for substantial axillary tumor burden (SATB). We explored the outcomes of limited axillary dissection (LAD, defined as sentinel lymph node (SLN) sampling or level 1 ALND) for SATB.

We retrospectively identified SATB patients who underwent LAD between 2011 and 2020. SATB was defined as gross extracapsular extension, ≥3 positive SLNs, palpable lymphadenopathy, or ≥3 suspected nodes on preoperative imaging. Those who received neoadjuvant chemotherapy or had follow-up <1 y were excluded.

We reviewed 4904 breast cancer cases and identified 33 women with SATB (tumor size 19.0 ± 9.8 mm, infiltrating ductal carcinoma 78.8%, estrogen receptor positive 100%, cN+ 66.7%) undergoing LAD during which 2(1-6) positive nodes out of 5(1-11) total nodes were resected. The intended axillary surgery was SLN sampling in 66.7%. During a median follow-up of 6.1(1.2-9.9) years, two cases of distal recurrence occurred; the 5-y disease-, metastasis-, and locoregional-free survival rates were 95.7%, 95.7%, and 100%, respectively. Survival probabilities for two control groups-a matched group of SATB patients undergoing ALND (n = 50) and those presenting with low axillary tumor burden (LATB, n = 137) did not differ significantly (all P > 0.3) when compared to SATB patients undergoing LAD. Higher KI67, larger tumor size, and omission of adjuvant radiotherapy correlated independently with disease recurrence among all node-positive patients (n = 249) undergoing axillary surgery.

Survival outcomes of LAD for SATB were comparable to ALND and to LATB patients, meriting further prospective investigation.