Predictors of Completion Axillary Lymph Node Dissection in Patients With Immunohistochemical Metastases to the Sentinel Lymph Node in Breast Cancer

Abstract

Axillary lymph node dissection (ALND) in patients with immunohistochemistry (IHC)-determined metastases to the sentinel lymph node (SLN) is controversial. The goal of this study was to examine factors associated with ALND in IHC-only patients. Retrospective review of an institutional SLN database from July 1997 to July 2003 was performed. We compared sociodemographic, pathologic, and therapeutic variables between IHC-only patients who had SLN biopsy alone and those that had ALND. Our study group consisted of 171 patients with IHC-only metastases to the SLN. Young age, estrogen receptor negative status, high Memorial Sloan-Kettering Cancer Center nomogram score, and chemotherapy were associated with ALND. Among patients who had ALND (n = 95), 18% had a positive non-SLN. Rates of systemic therapy were similar between those with and without positive non-SLNs at ALND. No axillary recurrences were observed in this series with a median follow-up of 6.4 years. The percentage of patients who were recurrence-free after 5 years was 97% (95% confidence interval, 92.1-98.6). On the basis of our findings and the lack of prospective randomized data, the practice of selectively limiting ALND to IHC-only patients thought to be at high risk and to patients for whom the identification of additional positive nodes may change systemic therapy recommendations seems to be a safe and reasonable approach.