SINODAR ONE, an ongoing randomized clinical trial to assess the role of axillary surgery in breast cancer patients with one or two macrometastatic sentinel nodes.

Sentinel lymph node biopsy alone is the current surgical axillary treatment for early-stage breast cancer patients with a negative sentinel lymph node (SLN). The possibility to omit axillary dissection also in presence of positive SLNs has been promoted by the American College of Surgeons Oncology Group (ASOCOG) Z0011 randomized trial. Several limitations and evidences of potential selection bias made this trial fairly controversial. Stronger evidence than currently available is needed on the safety of foregoing axillary dissection in well-defined populations of patients with positive SLNs. The Italian multicentre SINODAR ONE randomized trial here presented was designed with this aim.