Implications of lymphatic mapping for staging and adjuvant treatment of patients with breast cancer.

Lymphatic mapping has become a frequently used technique for staging the axilla in patients with breast cancer. In addition to sentinel nodes in the axilla, lymphoscintigraphy depicts sentinel nodes outside the axilla in up to 34% of patients. An increasing number of surgeons are now pursuing these extra-axillary nodes and are able to harvest them with limited morbidity in up to 87% of the patients concerned. Improved accuracy of staging is the result. Surgeons, radiotherapists and medical oncologists should consider the implications of the presence or absence of metastatic disease in such nodes. Incorporating the tumour status of these extra-axillary sentinel nodes in the management of patients will lead to a better selection of those who may benefit from postoperative radiotherapy to the internal mammary lymph node chain and from adjuvant systemic treatment.