Some People With Early-Stage Breast Cancer Don’t Need Axillary Lymph Node Surgery
Many people diagnosed with small, early-stage breast cancer and one or two cancer-positive sentinel lymph nodes may be able to skip axillary lymph node surgery and have only sentinel lymph node surgery, according to a study published on April 3, 2024, by The New England Journal of Medicine.
Key takeaways
Skipping more extensive axillary lymph node surgery and just having sentinel lymph node surgery — in which fewer lymph nodes are removed — led to the same five-year recurrence-free survival rates in people with small, early-stage, clinically node-negative breast cancer with one or two positive sentinel nodes.
“Clinically node-negative” means there are no physical signs of cancer in the lymph nodes and you and your doctor don’t feel any lumps there. There may still be small amounts of cancer in lymph nodes that can be seen when the nodes are removed and examined under a microscope.
About 90% of the people who had sentinel lymph node surgery and about 89% of the people who had axillary lymph node surgery were alive, with no cancer recurrence, five years after diagnosis.
About 90% of the people in the study received radiation therapy to the lymph nodes after surgery, as well as some type of systemic therapy, meaning a treatment that affects the whole body, such as hormonal therapy, targeted therapy, or chemotherapy.
What the results mean for you
If you’ve been diagnosed with early-stage breast cancer and have just one or two positive sentinel lymph nodes, you can skip axillary lymph node surgery. You will still need to have radiation treatment to the lymph nodes, along with any recommended hormonal therapy, targeted therapy, or chemotherapy, after breast cancer surgery.
Axillary lymph node surgery involves removing 10 or more lymph nodes, while sentinel lymph node surgery usually means removing just the one or two lymph nodes closest to the breast cancer. Because it removes more lymph nodes, axillary node surgery is linked to a higher risk of lymphedema, so most people would prefer to have sentinel node surgery, if possible.
“We want to perform less extensive procedures to spare patients from troublesome side effects,” lead author Jana de Boniface, MD, PhD, said in a statement. Dr. de Boniface is a breast surgeon at Capio Saint Goran’s Hospital and researcher at the Karolinska Institute, both in Sweden. “But we need to know that it's safe. Our assessment is that it is safe for patients to forgo axillary dissection if there are a maximum of two macrometastases [two metastatic lesions] in the sentinel lymph nodes. In these cases, axillary dissection is replaced with radiation therapy to the armpit, which results in less arm-related complications. This has now been implemented in clinical practice in Sweden.”
About the study
Called SENOMAC, this analysis included 2,540 people. All the people had been diagnosed with early-stage breast cancer in one breast. They all had breast cancer surgery that included sentinel lymph node removal.
The people ranged in age from 20 to 94, with most of them being in the 50 to 64 age range.
All the cancers had spread to one or two sentinel lymph nodes.
Most of the cancers (86.5%) were estrogen-receptor-positive and HER2-negative.
The spots of cancer in the lymph nodes were mostly very small, about the size of the point of a crayon.
After surgery, the researchers randomly assigned the people to have axillary lymph node surgery or not:
1,205 people had axillary lymph node surgery
1,335 people had only sentinel lymph node surgery
After surgery:
89.9% of people who had only sentinel lymph node surgery had radiation to the lymph nodes
88.4% of people who had axillary lymph node surgery had radiation to the lymph nodes
All but 26 people in the study had some type of systemic treatment, depending on the characteristics of the cancer.
Half the people were followed for longer than about four years and half were followed for a shorter time.
Recurrence rates, five-year overall survival rates, and five-year breast cancer-specific survival rates were similar for those who had axillary lymph node surgery and those who had sentinel lymph node surgery.
The researchers are continuing to follow the people in the study to see if overall survival — how long the people live whether or not the cancer comes back — is the same for both types of lymph node surgery.
Detailed results
Among the 1,335 people who had only sentinel lymph node surgery:
12 people (0.9%) had a local recurrence, meaning the cancer came back in the breast area
6 people (0.4%) had a regional recurrence, meaning the cancer came back in the lymph nodes near the breast
44 people (3.3%) had a distant recurrence, meaning the cancer came back in a part of the body away from the breast, such as the bones or liver
62 people (4.6%) died; 24 of them died due to breast cancer
Among the 1,205 people who had axillary lymph node surgery:
10 people (0.8%) had a local recurrence
6 people (0.5%) had a regional recurrence
53 people (4.4%) had a distant recurrence
69 people (5.7%) died; 31 of them died due to breast cancer
The researchers estimated five-year overall survival rates to be:
92.9% for people who had only sentinel lymph node surgery
92% for people who had axillary lymph node surgery
The estimated five-year breast cancer-specific survival rates were:
97.1% for people who had only sentinel lymph node surgery
96.6% for people who had axillary lymph node surgery
de Boniface, J. et al. Omitting Axillary Dissection in Breast Cancer with Sentinel-Node Metastases. N Engl J Med. Vol. 390 No. 13, 2024.
— Last updated on August 31, 2024 at 1:07 PM