Axillary dissection versus no axillary dissection in older patients with T1N0 breast cancer: 15-year results of a randomized controlled trial

To assess the role of axillary dissection in older breast cancer patients with a clinically clear axilla. Axillary dissection, once standard treatment for breast cancer, is associated with considerable morbidity. It has been substituted by sentinel node biopsy with dissection only if the sentinel node is positive. We aimed to determine whether axillary surgery can be omitted in older women, thereby sparing them morbidity, without compromising long-term disease control. We carried out a randomized clinical trial on 238 older (65-80 years) breast cancer patients, with clinically N0 disease of radiographic diameter 2 cm or less. Patients were randomized to quadrantectomy with or without axillary dissection. All received radiotherapy to the residual breast but not the axilla; all were prescribed tamoxifen for 5 years. Main outcome measures were overall survival and breast cancer mortality. We also assessed overt axillary disease in those who did not receive axillary dissection. After 15 years of follow-up, distant metastasis rate, overall survival, and breast cancer mortality in the axillary dissection and no axillary dissection arms were indistinguishable. The 15-year cumulative incidence of overt axillary disease in the no axillary dissection arm was only 6%. Older patients with early breast cancer and a clinically clear axilla treated by conservative surgery, postoperative radiotherapy, and adjuvant tamoxifen do not benefit from axillary dissection. This study was registered at clinicaltrials.gov (ID NCT00002720).