Validating a Predictive Model for Presence of Additional Disease in the Non–Sentinel Lymph Nodes of a Woman with Sentinel Node Positive Breast Cancer

Excerpt

Axillary dissection was performed for the staging of the axilla in essentially all women with breast cancer from the time of Halsted to the late 1990s. At that time, sentinel lymph node (SLN) biopsy was introduced and subsequently validated, and it proved to be a reliable, accurate method of staging the axilla with little associated morbidity. The purpose of SLN biopsy was to identify the approximately two-thirds of women with no disease in the axilla and to spare them the additional surgical procedure of axillary dissection. However, with the advent of SLN biopsy, a new conundrum has arisen. Although macrometastases in the SLN are often detected intraoperatively, micrometastases are often found on the histopathologic analysis that is only available several days after the procedure. And many clinicians have observed that most of these patients do not have any additional nodal disease identified if they undergo a completion axillary dissection. Furthermore, until the recent publication of a meta-analysis of the influence of locoregional control on mortality, there has been disagreement on the therapeutic benefit of removal of nodal disease. Therefore, some clinicians began advising their patients to not undergo completion axillary dissection, even though the sentinel node contained disease. …