SAN ANTONIO, TX—Sentinel lymph node (SLN) evaluation has revolutionized the surgical approach to the axilla in patients with breast cancer. Furthermore, recent trial results demonstrated that axillary lymph node dissection (ALND) can be safely omitted in select patients, according to a research presented at the 2015 San Antonio Breast Cancer Symposium.1
“Significant new evidence is emerging to help guide the management of patients with node-positive disease,” reported Reshma Jagsi, MD, DPhil, deputy chair, Department of Radiation Oncology, University of Michigan. Jagsi also suggests keeping patients informed and involved in the decision-making process to ensure that care is appropriately individualized.
The decision-making context has changed dramatically with the recent maturation of studies demonstrating low rates of axillary failure in select patients with clinically negative axillae and 1 to 2 positive sentinel nodes on sentinel lymph node biopsy (SLNB), even without completion ALND. ACOSOG Z0011 and IBCSG 23-01 trials demonstrated that low-risk patients may not need treatment beyond SLNB; MA.20 and EORTC 22922 trials, however, showed that some patients will benefit from adding comprehensive radiotherapy to ALND; a third trial, AMAROS, found that in clinically node-negative patients, ALND can be replaced with radiotherapy.
Risk factors to consider in determining optimal axillary management include number of nodes involved and number of nodes examined, size of nodal metastasis, extracapsular extension, age (younger patients), primary tumor size (large), medial primary tumor location, lymphatic vessel invasion, high grade, triple-negative subtype, and high recurrence score.
“SLNB alone is generally sufficient for patients with node-negative disease (including ITCs) and probably also those with very limited nodal involvement (micrometastases with favorable biology),” Jagsi explained. However, some directed axillary treatment—such as high tangent radiotherapy to the breast—may be appropriate in patients with increased risk of residual axillary disease despite systemic therapy, and more comprehensive nodal radiotherapy is appropriate for patients with higher risk, he continued.
In the setting of modern systemic therapy and lumpectomy with tangential breast radiotherapy, patients with low-volume metastases to the axilla may not need ALND or comprehensive nodal radiotherapy. Others with higher risk of harboring substantial residual nodal disease, however, may benefit from comprehensive nodal radiotherapy, Jagsi concluded.
1. Jagsi R. Contemporary role of RT in axillary management. Oral presentation at: San Antonio Breast Cancer Symposium; December 9-12, 2015; San Antonio, TX.