Axillary nodal status is the single best predictor of overall survival in women with breast cancer. The presence or absence of lymph node involvement has been an important determinant for the use of systemic adjuvant treatment. An axillary dissection also reduces the risk of axillary recurrence as a result of removing lymph nodes that contain cancer. Unfortunately, axillary lymph node dissection increases the risk of postoperative complications, including lymphedema, and increases the morbidity, hospital stay, recovery time, and cost of surgery. Research to date has been conflicting regarding the impact of age at diagnosis on late complications after full axillary nodal dissection. Two studies have reported older age at diagnosis to be a significant factor while a more recent study found younger age to be a risk factor for lymphedema, and yet another study revealed that age was unrelated to lymphedema incidence.

Using the newer sentinel node technique, a surgeon can identify patients with negative lymph nodes without performing a full axillary lymph node dissection. Sentinel lymph node biopsy entails injecting blue dye or radiolabeled colloid in the area of the breast lesion and following it out to the first lymph node that drains the cancerous area, the “sentinel” node.

This lymph node, or a small group of nodes, is then assessed for tumor involvement. The status of the sentinel node can be used to predict the status of the remaining nodes in the axilla. However, the procedure can be technically challenging, and the success rate varies according to the surgeon and the characteristics of the patient. When performed by experienced surgeons, the sentinel lymph node technique is minimally invasive and highly accurate. It can be performed successfully in more than 90% of eligible breast cancer patients, and the tumor status of the sentinel node accurately predicts the status of all axillary nodes in more than 95% of cases. It should be noted that sentinel node biopsy is appropriate only for patients with a clinically negative axilla. Sentinel lymph node evaluation has been shown recently to provide accurate staging in elderly patients as well as younger women.

The question of whether any form of axillary surgery (sentinel biopsy or a full dissection) is necessary has arisen based in part on studies assessing the utility and efficacy of node dissection in older women. For an increasing number of patients, systemic treatment decisions will not be affected by nodal status. In older women with breast cancer, decisions about the use of tamoxifen or chemotherapy can often be made based on the size and characteristics of the primary tumor. Although some women desire axillary dissection to obtain prognostic information, others will be content without this information if they can be spared surgery to the axilla and the potential associated morbidity. In women who have had conservative surgery and have a clinically negative axilla, axillary irradiation can be administered at the same time as breast irradiation to prevent axillary recurrence. The evaluation and management of the axilla has become increasingly complex in recent years. The options are varied, and physicians should carefully consider the treatment goals and a patient’s preferences in the decision-making process.