Objective: The aim of this multicenter randomized trial was to assess the efficacy and safety of sentinel lymph node (SLN) biopsy compared with axillary lymph node dissection (ALND).
Background: All studies on SLN biopsy in breast cancer report a variable false negative rate, whose prognostic consequences are still unclear.
Methods: From May 1999 to December 2004, patients with breast cancer < or =3 cm were randomly assigned to receive SLN biopsy associated with ALND (ALND arm) or SLN biopsy followed by ALND only if the SLN was metastatic (SLN arm). The main aim was the comparison of disease-free survival in the 2 arms.
Results: A total of 749 patients were randomized and 697 were available for analysis. SLNs were identified in 662 of 697 patients (95%) and positive SLNs were found in 189 of 662 patients (28.5%). In the ALND group, positive non-SLNs were found in 18 patients with negative SLN, giving a false negative rate of 16.7% (18 of 108). Postoperative side effects were significantly less in the SLN group and there was no negative impact of the SLN procedure on psychologic well being. At a median follow-up of 56 months, there were more locoregional recurrences in the SLN arm, and the 5-year disease-free survival was 89.9% in the ALND arm and 87.6% in the SLN arm, with a difference of 2.3% (95% confidence interval: -3.1% to 7.6%). However, the number of enrolled patients was not sufficient to draw definitive conclusions.
Conclusion: SLN biopsy is an effective and well-tolerated procedure. However, its safety should be confirmed by the results of larger randomized trials and meta-analyses.