Internal mammary sentinel nodes in primary breast cancer.

For over a century, there has been considerable interest in the management of regional lymph node metastasis in patients with primary breast cancer. Since the advent of sentinel lymph node biopsies, there has been renewed interest in the management of patients with metastasis to the internal mammary nodes. The appropriate management of these patients has not yet been established. Some investigators propose that biopsy of the internal mammary sentinel node may provide additional prognostic information which might be used to guide the administration of systemic adjuvant therapy. Additionally, it has been suggested that patients with metastasis to the internal mammary sentinel node may benefit from radiotherapy to the internal mammary nodal chain. Clinical trials are needed to resolve these issues. Internal mammary sentinel node biopsy in patients with primary breast cancer should be considered investigational, and conducted only in the context of clinical trials.