Breast: Axillary management (AMAROS)

Why B is correct

AMAROS randomised patients with cT1-2 clinically node-negative breast cancer and a positive sentinel node to axillary dissection or axillary radiotherapy, finding both gave very low axillary recurrence (5-year 0.43% vs 1.19%) but significantly less lymphoedema with radiotherapy. Where axillary treatment is indicated, axillary radiotherapy is preferred over completion dissection because of lower arm morbidity.

And why the others are not

• AIncorrect. Completion axillary dissection gives equivalent control but significantly more lymphoedema than axillary radiotherapy in AMAROS.
• CIncorrect. Axillary treatment was deemed necessary in this scenario, so omitting treatment entirely is not the comparison being asked.
• DIncorrect. Combining radiotherapy and dissection compounds toxicity, including a high lymphoedema rate, without added benefit.
• EIncorrect. Ultrasound surveillance is not an established substitute for indicated axillary treatment in node-positive disease.

Source EORTC 10981-22023 AMAROS - axillary radiotherapy vs ALND — Donker M, van Tienhoven G, Straver ME, et al. Radiotherapy or surgery of the axilla after a positive sentinel node in breast cancer (EORTC 10981-22023 AMAROS): a randomised, multicentre, open-label, phase 3 non-inferiority trial. Lancet Oncol. 2014;15(12):1303-1310. 10-year results: Bartels SAL, et al. J Clin Oncol. 2023;41(12):2159-2165.