Advances in Surgical De-escalation and Systemic Therapy in HR-Positive, HER2-Negative Breast Cancer

Key clinical trials show that, in patients with limited sentinel-node metastases, omitting ALND—when combined with whole-breast or regional nodal radiotherapy—provides comparable local control and survival while reducing arm morbidity and lymphedema. These data shift the operative risk–benefit balance, making less‑invasive axillary staging the practical default in surgical planning.

Routine completion ALND has given way to sentinel lymph node biopsy for many patients with early, HR‑positive, HER2‑negative tumors. Trials enrolling patients with one to two positive sentinel nodes and using adjuvant radiotherapy report equivalent local control and survival alongside clearly lower surgical morbidity. As a result, SLNB has emerged as the de‑escalated default for eligible patients.

Nodal status alters absolute recurrence risk and therefore eligibility for node‑count–dependent adjuvant agents. Accurate surgical staging therefore provides essential pathological information that informs whether to add therapies with proven benefit and remains foundational to systemic treatment decisions.

Thresholds for nodal burden typically separate node‑negative from node‑positive disease and distinguish low‑volume (one to two nodes) from higher‑volume involvement. These distinctions inform eligibility for CDK4/6 inhibitors and, in biomarker‑selected patients, PARP inhibitors; careful pathological nodal assessment therefore influences both regimen selection and risk counseling.

Patient‑centered outcomes after de‑escalation include lower lymphedema rates and fewer functional arm problems, while oncologic outcomes remained unchanged in the studied cohorts. Clinicians must balance less‑invasive surgery with comprehensive systemic planning and active surveillance for late toxicities—eg, cardiotoxicity from some adjuvant agents. Multidisciplinary coordination is required to preserve quality of life without compromising efficacy.