Predictors of High-Burden Residual Axillary Disease After Neoadjuvant Therapy in Breast Cancer.

BACKGROUND

Neoadjuvant therapy (NAT) plays a crucial role in breast cancer (BC) management by enabling tumor and nodal downstaging. While axillary lymph node dissection (ALND) remains the standard for patients with residual nodal disease after NAT, its prognostic benefit is debated. Identifying predictors of high-burden residual axillary disease may guide treatment intensification and surgical de-escalation strategies.

METHODS

We retrospectively analyzed 262 BC patients treated with NAT followed by ALND between 2006 and 2023. Patients were stratified into low- (ypN0-mi-1) and high-burden (ypN2-3) residual axillary disease groups. Univariate and multivariate logistic regression analyses were performed to identify independent predictors of high-burden residual disease.

RESULTS

High-burden residual axillary disease was observed in 35.9% of patients. Baseline cN+ status (OR = 7.697, = 0.013), HR+/HER2- subtype (OR = 3.945, = 0.003), and larger post-NAT tumor size (OR = 1.043, < 0.001) were independent predictors.

CONCLUSIONS

Identifying patients at risk of high-burden residual axillary disease is essential to optimize neoadjuvant strategies. Increasing axillary pathological complete response may reduce the need for ALND, minimizing surgical morbidity without compromising oncological outcomes.