Introduction: Axillary node status is a predictor of breast cancer survival. Axillary node dissection (ALND) following positive sentinel node biopsy (SLNB) is challenged by the American College of Surgeons Z0011 trial, where clinically/radiologically node-negative, SLNB positive early stage patients failed to derive therapeutic benefit from ALND at 6 years.
Aims: To quantify the rates of non-sentinel lymph node positivity after ALND in all breast cancer stages. To assess Z0011 trial result application to an Irish patient population.
Methods: Retrospective review of a prospectively maintained database of clinically node-negative patients undergoing breast conserving surgery and ALND for a positive SLNB from January 2011 to January 2012.
Results: Of 174 new breast cancers diagnosed, 144 underwent surgery of which 127 patients were clinically/radiologically node-negative; 46 patients were SLNB positive; 34 (73.9 %) proceeded to ALND. Of 9 T1 tumours, 3 (33.3 %) had further positive nodes on ALND. Of 24 T2 tumours, 11 (45.8 %) had further positive nodes on ALND. All 3 (100 %) T3/T4 tumours had further positive nodes on ALND. Mean numbers of sentinel and axillary nodes harvested were 2.3 and 15.2, respectively. In the SLNB positive, ALND negative group, 12 of 18 (66.7 %) patients were <60 years versus 14 of 17 (82.4 %) in the SLNB positive, ALND positive group. This may be indicative that younger women have a trend toward node positivity following ALND for a positive SLNB.
Conclusion: These data suggest that a significant proportion (41.9 %) of T1/T2 tumours undergoing ALND following positive SLNB have further positive nodes. It may be premature to exclude ALND in patients with T1/T2 tumours following a positive SLNB.