[Axillary lymph node dissection versus axillary radiotherapy in patients with a positive sentinel node: the AMAROS...

To investigate whether axillary radiotherapy (ART) in patients with primary breast cancer and a tumour-positive sentinel node results in a similar axillary tumour recurrence rate compared with axillary lymph node dissection (ALND), and whether ART results in lower morbidity.

Randomised, multicentre non-inferiority trial.

Patients with breast cancer ≤ 5 cm without clinical signs of lymph node metastases but with a tumour-positive sentinel node were randomised between ALND or ART. The primary endpoint was the 5-year axillary recurrence rate. Secondary endpoints were disease-free survival, overall survival, morbidity (lymphoedema and shoulder function) and quality of life. (www.clinicaltrials.gov, study number NCT00014612.)

Between 2001 and 2010, 1425 patients with a tumour-positive sentinel node were included, 744 of whom had been randomised to ALND and 681 to ART. After a median follow-up period of 6.1 years, the 5-year axillary recurrence rate was 0.43% after ALND and 1.19% after ART; the difference was not statistically significant. The primary analysis was underpowered due to the low number of axillary recurrences. At 5 years the disease-free survival rate was 86.9% after ALND and 82.7% after ART. Overall survival was 93.3% and 92.5% respectively. Lymphoedema was noted significantly more often after ALND than after ART at 1 year, 3 years and 5 years. There were no significant differences in shoulder function or quality of life.

Both ART and ALND produce very low axillary recurrence rates in patients with breast cancer ≤ 5 cm and a tumour-positive sentinel node. ART results in significantly less lymphoedema than ALND.