New surgical procedure targets cancerous lymph nodes

A new procedure developed by MD Anderson surgeons is helping doctors determine which lymph nodes in breast cancer patients are cancerous and which are cancer free, resulting in the need to remove fewer lymph nodes.

Until recently, the standard of care for patients whose breast cancer had spread was to undergo a complete axillary lymph node dissection, in which 10 or more lymph nodes are removed from the armpit area. This sometimes resulted in lymphedema — painful swelling of the soft tissues in the arm caused by a buildup of lymph fluid. The condition can happen days, months or even years after surgery, and may be temporary or ongoing.

“Axillary lymph node dissection is one of the most challenging procedures for breast cancer patients to recover from and can have lifelong effects,” says Abigail Caudle, M.D., assistant professor of Breast Surgical Oncology. It makes sense, Caudle says, that doctors remove as few lymph nodes as possible while still removing all that contain cancer.

A less severe procedure, called sentinel lymph node removal, involves removing only one or a few key lymph nodes. The procedure is useful in assessing disease status, but it can miss cancer in 10% to 15% percent of women.

Before breast cancer surgery, a patient typically undergoes chemotherapy to shrink the breast tumor, so less tissue needs to be removed. Research suggests that chemo before surgery also destroys cancer cells in the lymph nodes in 40% to 70% of women, eliminating the need for extensive lymph node removal surgery.

“We just haven’t had a good way to determine which patients converted to node-negative status, and therefore we’ve been subjecting too many women to unnecessary surgery,” said Caudle, who conducted a study of a new procedure to identify and remove cancerous lymph nodes while leaving noncancerous lymph nodes in place.

Named targeted axillary dissection, or TAD, the procedure involves placing tiny tags on lymph nodes that are biopsied and found to be cancerous. The tags will allow surgeons to locate the nodes later, when surgery is performed.

After tags are in place, patients undergo chemotherapy. Once chemo concludes, surgery is performed and pathologists examine the clipped nodes to see if cancer is still present.

The TAD procedure involves removing sentinel lymph nodes (those closest to the tumor), as well as the tagged nodes.

“This surgery may allow up to 40% of women who are diagnosed with axillary metastasis and undergo chemotherapy before surgery to avoid more extensive and often debilitating surgery,” said Henry Kuerer, M.D., Ph.D., professor of Breast Medical Oncology, who also conducted the study. “Our findings epitomize precision surgery in that we are specifically targeting the known disease and limiting the morbidity for our patients.”

This research, published in the Journal of Clinical Oncology, has changed treatment guidelines at MD Anderson for a select group of breast cancer patients with lymph node metastasis, who will now receive targeted axillary dissection (TAD).

Read more about this study on MD Anderson’s website.