Are Clinically Node-Negative Patients with a Positive Preoperative Axillary Lymph Node Biopsy Appropriate Candidates for Sentinel Lymph Node Biopsy?

Background: Whether cN0 patients with image-detected nodal metastases are appropriate for sentinel lymph node biopsy (SLNB) or should proceed directly to axillary lymph node dissection (ALND) or neoadjuvant chemotherapy (NAC) is controversial. We sought to determine how often ALND is needed with upfront surgery and to identify factors associated with ≥ 3 positive SLNs after a positive preoperative lymph node (LN) biopsy.

Methods: Patients with cT1-2N0 breast cancer and a positive LN biopsy treated from 2014 to 2022 were identified from a prospective database. Patients who received NAC were excluded. Clinicopathologic characteristics were compared between women with 1-2 positive SLNs and ≥ 3 positive SLNs.

Results: Of 90 eligible patients, 66 (73%) had 1-2 positive SLNs and 24 (27%) had ≥ 3 positive SLNs. The median patient age was 62 years, median tumor size was 2.2 cm, and 16 women (18%) received a mastectomy. There was no difference in body mass index, tumor size, histology, grade, multifocality, presence of lymphovascular invasion, and receptor status between groups. On multivariable analysis, having ≥ 3 positive SLNs was associated with > 1 abnormal LN on preoperative imaging (odds ratio [OR] 4.36, 95% confidence interval [CI] 1.47-14.0; p = 0.01), microscopic extracapsular extension in the SLNs (OR 3.83, 95% CI 1.25-13.7; p = 0.025), and a higher median number of SLNs removed (OR 1.42, 95% CI 1.10-1.88; p = 0.01).

Conclusions: More than 70% of women with cT1-2 breast cancer with image-detected nodal metastases had < 3 positive SLNs and did not require ALND. To avoid multiple trips to the operating room, frozen section can be considered in women with multiple abnormal LNs on imaging.