Palpable Adenopathy Does Not Indicate High-Volume Axillary Nodal Disease in Hormone Receptor-Positive Breast Cancer

Axillary metastases in the form of palpable adenopathy indicate the need for neoadjuvant chemotherapy or axillary lymph node dissection (ALND). Patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) disease infrequently have nodal pathologic complete response to neoadjuvant chemotherapy and often require ALND. Sentinel lymph node biopsy is an accepted treatment for patients with two or fewer non-palpable nodal metastases who are undergoing breast conservation. The proportion of patients with HR+/HER2- disease with palpable adenopathy and two or fewer nodal metastases is unknown.

Patients with cT1-T3N1 HR+/HER2- disease with palpable adenopathy were identified from a prospective database. Patients who underwent mastectomy or breast-conserving therapy with ALND were included in this study, whereas patients who received neoadjuvant chemotherapy were excluded. Clinicopathologic characteristics were compared between patients with two or fewer or more than two positive nodes on ALND.

Of 180 patients included, 78 (43%) had two or fewer positive nodes on ALND, including 40/72 patients (56%) who underwent lumpectomy. On univariate analysis, cT1 tumor, unifocal tumor, only one palpable node, and two or fewer suspicious nodes on ultrasound were associated with two or fewer positive nodes on ALND. On multivariable analysis, number of suspicious nodes on ultrasound and cT stage were independently associated with two or fewer positive nodes on ALND.

A substantial minority of patients with cT1-3N1 HR+/HER2- disease with palpable adenopathy had two or fewer positive nodes on ALND. Standard clinicopathologic features and ultrasound findings can help identify candidates for upfront sentinel lymph node biopsy as a strategy to avoid ALND. Prospective studies evaluating this approach are warranted.