Pretreatment Axillary Nodal Volume as a Prognostic Factor for Breast Cancer

Background and Objectives: We evaluated the prognostic value of pretreatment axillary nodal volume in breast cancer patients treated with neoadjuvant systemic therapy. Methods: We retrospectively reviewed 302 breast cancer patients with biopsy-proven axillary LN involvement who received neoadjuvant systemic therapy. Axillary nodal volumes were obtained from pretreatment magnetic resonance imaging. Univariate and multivariate analyses for disease-free survival (DFS) and overall survival (OS) rates were conducted. Results: The median follow-up period was 57.0 months, and 5-year DFS and OS rates were 81.6% and 91.9%, respectively. Pretreatment axillary nodal volume ranged from 0.2 mL to 134.2 mL, and the first tertile (2.6 mL) and fifth quintile (12.0 mL) were chosen as the optimal cutoff points for survival outcomes. In the multivariate analysis, nodal volume (< 2.6 mL vs. 2.6-12.0 mL vs. ≥ 12.0 mL) was a significant prognostic factor for DFS (5-year DFS, 90.1% vs. 79.6% vs. 72.2%) and OS (5-year OS, 97.9% vs. 90.9% vs. 84.2%), whereas the N stage was not. Conclusions: In breast cancer patients treated with neoadjuvant systemic therapy, larger pretreatment axillary nodal volume was associated with poor survival outcomes.