Patterns of Failure in Women Who Have Residual Nodal Disease After Neoadjuvant Chemotherapy for Breast Cancer According to Extent of Lymph Node Surgery

This study assessed patterns of failure of 70 patients with 1 to 3 involved nodes after neoadjuvant chemotherapy for breast cancer based on type of axillary surgery (sentinel lymph node biopsy alone vs. completion axillary dissection). We did not find differences in patterns of recurrence between the 2 groups. Background: Optimal surgical management of limited axillary nodal disease following neoadjuvant chemotherapy (NAC) for breast cancer is evolving. Concerns exist with respect to leaving residual disease in the axilla when omitting axillary lymph node dissection (ALND) in this setting. We sought to determine whether extent of nodal surgery altered patterns of failure and patient outcomes. Patients and Methods: We identified 70 patients with breast cancer who were confirmed cNO after NAC yet had residual nodal disease (ypN1) on sentinel lymph node biopsy (SLNB). Twenty-eight patients underwent SLNB alone and 42 underwent SLNB completion (c)ALND in a non-randomized fashion. Most (n = 65) patients underwent adjuvant regional nodal irradiation (RNI). Detailed patterns of failure data were obtained for each patient. Results: The median follow-up was 43.5 months. There were 30 (43%) recurrences. Of these, 5 were isolated locoregional failures, and 24 were distant failures. There were no significant differences in local (P = .13), regional (P = .62), or distant (P = .47) failure between patients who underwent SLNB alone versus SLNB = cALND. Seventeen (24%) patients died. Overall survival was similar in both groups with median overall survival not reached for those who underwent SLNB and 109 months for those who underwent SLNB + cALND (P = .45). Conclusions: There were no differences in patterns of recurrence among patients with 1 to 3 involved lymph nodes after NAC who underwent SLNB alone versus SLNB + cALND in the setting of RNI. We await the results of ongoing, prospective clinical trials to confirm the relative merits of RNI in lieu of cALND in these patients. (C) 2020 Elsevier Inc. All rights reserved.