Stage migration with sentinel node biopsy in breast cancer

BackgroundAxillary staging provides the single most important piece of prognostic information in breast cancer patients. This retrospective study was performed to document the phenomenon of stage migration.MethodsOf 392 patients, 5 (1%) failed identification of sentinel lymph nodes (SLNs) and therefore underwent axillary lymph node dissection (ALND). Four patients (80%) had metastatic lymph nodes, 302 (77%) patients had negative SLNs, 47 (15%) underwent ALND, 85 (22%) had positive SLNs, 11 (13%) received adjuvant radiation treatment to the axilla, and 74 (87%) underwent completion ALND.ResultsThe median (quartiles) follow-up period was 29 months (19–46 mo). Twenty of 392 (5%) patients had disease relapse; 2 of which were local (.5%) and the rest were systemic. Earlier relapse was related significantly to lymph node status, tumor grade, and tumor size. SLN-negative patients who did not receive ALND had a relapse rate of 2.3% (6 of 256) compared with 0% in those who were truly negative based on confirmatory ALND. SLN-positive patients who did not receive ALND had a 9% (1 of 11) relapse rate.DiscussionThe stage-matched pattern of relapse between SLN biopsy and ALND patients revealed lower relapse rates in SLN biopsy–staged patients, documenting the stage migration phenomenon.