A study conducted recently at MD Anderson confirmed that most women with early-stage breast cancer who undergo less aggressive lymph node removal fare just as well as those who undergo more extensive removal.
This finding is important because for years women with breast cancer underwent either a mastectomy or a lumpectomy to remove the tumor, followed by another procedure to remove 10 or more lymph nodes from under the affected armpit.
Known as axillary nodes, they drain lymph fluid from the breasts and surrounding areas into the lymphatic system, which can then spread the breast cancer cells to other parts of the body.
“The thought in the past was if you remove the axillary nodes, you can stop the cancer’s spread,” says Kelly Hunt, M.D., professor of Surgical Oncology.
But a groundbreaking study conducted in 2011 by the American College of Surgeons Oncology Group revealed that early-stage breast cancer patients whose axillary lymph nodes were removed were just as likely to be alive and cancer-free five years later when compared to women who had only their sentinel lymph nodes removed. Sentinel nodes are the first few lymph nodes into which a tumor drains.
“Researchers attribute this to chemotherapy or radiation, which are often prescribed to shrink a tumor before surgery. They believe the chemo and radiation probably killed the cancer cells in the axillary lymph nodes,” explains Hunt.
This was good news for cancer patients. Axillary node removal can cause debilitating, lifelong side effects such as arm swelling, numbness, nerve damage and range-of-motion problems.
But the question remained: Could this change in practice really impact a substantial portion of breast cancer patients?
To arrive at an answer, MD Anderson recently conducted a study of almost 900 patients with early-stage (stage I or II) breast cancer. Some patients underwent sentinel node removal, while others had axillary nodes removed. In addition, some patients opted for breast-conserving therapy (lumpectomy with radiation), while others opted for total mastectomy.
After adjusting for tumor stage, the research team found no significant differences in survival between women undergoing sentinel node removal versus axillary node removal. Furthermore, outcomes were similar for women who had undergone a mastectomy versus breast-conservation therapy.
“Armed with data from the 2011 trial and this new trial, we can say if no more than one or two sentinel lymph nodes test positive for cancer, you can have breast-conservation therapy and avoid axillary node removal, because we know your survival will not be impacted by leaving the rest of the nodes intact,” explains Hunt, co-author of the study. “We’re not saying that axillary node removal should be eliminated, but we should use it more wisely so that a huge percentage of patients don’t have to suffer the long-term complications of such an aggressive procedure.”
In terms of mastectomy versus breast conservation, Hunt says women sometimes assume mastectomy is the safer option.
“Usually they say it offers them more peace of mind, but we now know survival is not different between the two procedures for women with early-stage breast cancer.”