As previously stated, good responses in the axilla after NET are rarely expected, so this might create more difficulties when carrying out a SLNB. Nevertheless, data regarding surgical management of the axilla after NET is limited. Three trials have proven sentinel node biopsy (SLNB) to be a safe technique when cN1 axilla changed to cN0 after NCT, and this has brought about a widespread change in practice patterns, with a general avoidance of AD when a complete response is presumed. Īxillary management after NCT has been a controversial issue in the past few years, mainly because of the concern that disease may be left behind if an axillary dissection (AD) is not performed. 15.26%, p 6 months) seems to increase the likelihood of nodal pCR. As reported by other authors, lobular breast cancer had a significantly lower percentage of nodal pCR when compared to ductal histologies (12.4% vs. In a recent review, Stafford et al., after analyzing 4580 ER+ N+ breast cancers from the National Cancer Database, concluded that nodal pCR could be achieved in up to 14.5% of patients. A slight increase in these rates was observed by Rusz et al., reaching 13% node pCR in N+ patients after one year of NET with letrozole. Most authors find that NET is less likely to de-escalate surgery in the axilla than in the breast, even though pCR rates range from 1.3% to 11%. Unfortunately, although axillary-positive patients have been included in most NET trials, very little has been concluded regarding changes brought about by endocrine treatment at this level.
It is well established that, after NCT, ER+/HER-2 negative tumors do not achieve a good response in both breast and axilla, with pCR rates below 15%. These advantages have established neoadjuvant chemotherapy (NCT) as a widely accepted approach to estrogen receptor negative (ER−) tumors, but neoadjuvant endocrine therapy (NET) still remains an underutilized tool for ER+ breast cancers, and is frequently relegated to the treatment of elderly or frail patients who are not candidates for chemotherapy. Finally, neoadjuvant treatment provides a unique opportunity for validating new treatments, alone or in combination, given that results can be obtained in short periods of time. On the other hand, assessing the in vivo response enables us to determine drug efficacy, as well as to study any biological or molecular changes that may lead us to explore new biomarkers. In the first place, tumor downstaging may be achieved, thus increasing breast-conserving surgery (BCS) rates and, in some cases, reducing axillary dissection. In recent years, the neoadjuvant or presurgical approach has established itself as a very useful strategy in breast cancer management, because it offers numerous advantages. ET is a key pillar in the treatment of ER+ tumors, since it has widely demonstrated its efficacy in improving survival and reducing recurrences.