What is sentinel node biopsy?
The sentinel lymph node, also called the guard node, is the lymph node in the arm pit where breast cancer will first spread. The surgeon uses either a special blue dye or radioactive isotope (or in some cases both) which is injected into the breast prior to surgery.
The dye or isotope used then moves from the tumor to the lymphatic system. The first node to turn blue or contain the radioactive material is referred to as the sentinel node. The first node that turns blue (using the dye method) or that is hot with the Geiger Counter (using the radioactive isotope) is removed and immediately examined by the pathologist
Sentinel Node Biopsy
A sentinel node biopsy determines if breast cancer has spread to the lymph nodes. An important part of staging cancer, it impacts recommendations for a patient's treatment. At Johns Hopkins, the sentinel node biopsy is the standard of care for determining the presence of cancer in the axillary lymph nodes.
How do sentinel node biopsy results affect treatment?
If it is negative for tumor cells then the remaining lymph nodes are left intact, reducing the risk of lymphedema in the future, as well as preserving healthy tissue that doesn’t need to be surgically disturbed. However, if the node is positive, other nearby nodes need to be examined for cancer. The pathology report of the sentinel node is sent while the surgeon is still in the operating room, which allows the surgeon to proceed with an axillary node dissection if necessary and saves the patient a second surgery.
At the Johns Hopkins Breast Center, our surgeons have been performing sentinel node biopsies since 1996, when they began as clinical trials. Because of our work—and that of colleagues at other centers—sentinel node biopsy is now the standard of care for determining the presence of cancer in the axillary lymph nodes.
Knowing if the cancer has spread to the nearby lymph nodes is a critical part of staging, and therefore impacts the recommendations for treatment of the patient’s breast cancer.