Axillary Radiotherapy or Axillary Lymph Node Dissection in Patients With Clinically Node- Positive Breast Cancer Undergoing Upfront Tailored Axillary Surgery

Despite major morbidity, axillary lymph node dissection (ALND) is standard of care in patients with clinically node positive breast cancer (cN+ BC) who undergo upfront surgery, which is frequently indicated in case of luminal biology. Tailored axillary surgery (TAS) was shown to selectively target positive nodes, thereby removing significantly more nodes than sentinel lymph node biopsy (SLNB), but less nodes than ALND. Therefore, it is currently unclear if TAS in combination with axillary radiotherapy (ART) exposes the axilla to less harm compared to ALND. It is hypothesized that patient's quality of life (QoL) and morbidity can be improved by replacing ALND with the combination of TAS and ART in patients undergoing upfront surgery. The main goal of this trial is to investigate if in patients with clinically node positive breast cancer undergoing upfront surgery, treatment with TAS and ART is superior to ALND in terms of arm-related QoL and occurrence of lymphedema two years after randomization.