EBCC-11: Sentinel Lymph Node Biopsy in Triple-Negative and HER2-Positive Breast Cancers
Sentinel lymph node biopsies may be safely avoided for some women, according to research presented at the 11th European Breast Cancer Conference (EBCC-11). Two new studies show that women with either triple-negative or HER2-positive types of breast cancer, whose cancers respond well to chemotherapy given before surgery, are at very low risk of having any cancer cells in the sentinel lymph nodes.
Neoadjuvant Chemotherapy
The first study was by a team at University Hospital Vall Hebron, Barcelona, led by breast surgeon Christian Sisó, MD (Abstract 104). These investigators studied a group of 90 patients treated at the hospital between January 2011 and December 2016. All had either HER2-positive or triple-negative breast cancer.
All patients were given neoadjuvant chemotherapy prior to surgery. They were also given ultrasound scans to check for signs of cancer in the lymph nodes, and this was confirmed with pathology tests.
Overall, 54 patients (60%) had no obvious signs of cancer in their lymph nodes before treatment. Following chemotherapy, all but two (96.3%) had no cancer cells in their lymph nodes. Twenty-three of these women (42.5%) also had no cancer cells growing in the breast, and none of those had cancerous cells in their lymph nodes.
Of the remaining 36 patients (40%) who did have signs of cancer in their lymph nodes before treatment, 17 (47.2%) had no cancer cells growing in the breast after treatment and, of these, 13 (76.5%) were also free of cancer cells growing in their lymph nodes.
Dr Sisó explained, “Our results suggest that giving chemotherapy to patients with these types of breast cancer before considering surgery offers the possibility of reducing or even avoiding surgery. By giving drug treatment first, we are able to see how well the drugs work against an individual tumor. If they are working well, they can clear cancer cells from the lymph nodes and in the breast.”
He continued, “In women who had no signs of cancer in their lymph nodes and where treatment seems to have cleared the cancer in the breast, lymph node surgery might be avoided. On the other hand, in women who had signs of cancer in their lymph nodes before treatment, there is still a risk that the disease will remain there, even when it has been successfully treated in the breast itself.”
Upfront Chemotherapy
The second study (Abstract 20) was presented by Marieke van der Noorda, MD. This study was performed by the breast cancer team at the Netherlands Cancer Institute–Antoni van Leeuwenhoek Hospital.
They studied a group of 294 patients with breast cancer treated at the institute between January 2013 and September 2017. All had no signs of cancer in their lymph nodes according to ultrasound, positron-emission tomography/computed tomography, or cytology by fine-needle aspiration. All patients were treated with upfront chemotherapy.
Following chemotherapy, none of the patients with HER2-positive breast cancer had tumor cells in their sentinel lymph nodes and almost none (1%) with triple-negative tumors had cancer cells in their lymph nodes. Only 2% of patients with a poor-grade tumor had cancer cells in their lymph nodes. All patients whose breast tumors responded completely to the chemotherapy were also cancer-free in their lymph nodes.
Dr. van der Noordaa explained, “These results suggest that sentinel lymph node biopsies are most likely not needed in many women who undergo upfront chemotherapy and who have no sign of cancer in their lymph nodes before the start of chemotherapy. This could mean the side effects of sentinel lymph node biopsies could be prevented in these women.”
Following this work, Dr. van der Noordaa will start a trial (ASICS) for patients with HER2-positive or triple-negative breast cancer and poor-grade tumors who are treated with upfront chemotherapy to evaluate whether avoiding sentinel lymph node biopsies results in recurrences in the lymph nodes and to examine overall survival and quality of life.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
