Background and methods: Sentinel lymph node (SLN) biopsy is a useful way of assessing axillary nodal status in breast cancer patients. Recently, several surgeons have begun to abandon routine axillary dissection on the basis of negative SLN biopsy results. However, there is no long-term data comparing outcomes of SLN biopsy alone with those of axillary dissection. This paper reviews and discusses the significance of ongoing prospective randomized clinical trials aiming at the elimination of axillary dissection.
Results: SLN biopsy is known to have a false-negative rate. It can thus be assumed that SLN biopsy alone may fail to remove the disease completely from the axilla in some patients. As a result, it is not known whether SLN biopsy alone will increase the axillary recurrence rate, particularly in patients with a high risk of axillary lymph node metastasis. Recently, moreover, locoregional control appears to be important for enhancing survival in conjunction with adjuvant systemic therapy. It is therefore still unclear to what extent the benefits of SLN biopsy outweigh the risks and, if so, for which patient groups.
Conclusion: Before SLN biopsy can replace routine axillary dissection, research using long-term regional controls and investigation of survival in a prospective randomized trial are essential. Except for clinical research studies, routine axillary dissection should not be abandoned until and unless there is documentation of extensive experience and a low false negative rate. Even with such evidence, however, patients undergoing SLN biopsy without concomitant axillary dissection should be informed of the risk of a false-negative result.