Sentinel lymph node biopsy (SNB) is a relatively recent advance in the treatment of breast cancer. Our team has been performing this procedure since 1996 It reduces the amount of surgery a patient needs to have.
Lymph nodes are a part of the system that fights infections. These nodes act as a barrier to the spread of infection by destroying bacteria and avoiding, in turn, their entry into the bloodstream. Cancer usually spreads through the lymph system. Breast cancer usually spreads to the nodes located under the arm (armpit).
Breast cancer is being diagnosed at earlier and earlier stages, so axillary dissection in 80% of these patients shows that nodes in that area are not afected. By means of the SNB, this type of patients can avoid the axillary dissection.
The SNB detects the first nodes where the tumor spreads, called sentinel nodes. In the Nuclear Medicine Department, a radioactive substance is injected around the tumor prior to the surgery. That substance follows the same path than the tumor cells are likely to follow to the axillary nodes.
In order to indentify the SN (sentinel node) within the operating theatre, the surgeon uses a device detecting radioactivity .The most radioactive node is the sentinel node. Once the node(s) is removed in the operating theatre, it is determined whether or not there are tumor cells. Should the node(s) not contain tumor cells, no further surgery is performed in the armpit and, thus, a full axillary dissection is avoided. Should the sentinel node contain tumor cells, a full axillary dissection is then performed.
The SNB is more advisable than axillary dissection. One of the main advantages is to reduce the impact of lymphedema (arm edema) and to diminish surgical complications.