Lymph node surgery

Sentinel nodes

Sentinel lymph nodes (there are often 2 or 3) are the first lymph nodes that drain lymph from the breast (and therefore the tumor cells that may be circulating in them). To identify them, a “marker” is injected into the breast to diffuse into the lymph nodes. Two products are used: a dye (injected at the beginning of the procedure) and/or an isotope tracer (usually injected the day before).

The surgeon then removes the sentinel lymph nodes for analysis: if no tumor cells are found, the other lymph nodes in the armpit are presumably unscathed. This technique reduces the number of lymph nodes removed compared to axillary dissection, thus reducing the risk of postoperative sequelae.

Axillary node involvement is an important consideration in planning breast cancer treatment.

The lymph nodes taken are analyzed by the pathologist, sometimes even during the operation. The data from the final analysis are available a few days after the operation. This examination is important to define the post-operative treatments (radiotherapy, chemotherapy…).

Extemporaneous examination of sentinel lymph nodes

1. Apposition of the ganglion on slide
2. Staining of the slide
3. Node apposition cytology

1. Invaded sentinel node
2. Isolated tumor cells

The axillary dissection

Axillary dissection is performed in case of invasive cancer with lymph node invasion. The classic axillary dissection only removes the lymph nodes in the lower part of the armpit, usually about ten out of the forty nodes in the armpit. Rarely, when there is significant involvement of the armpit, a more extensive dissection must be performed to remove all the affected nodes. Lymphoedema (edema of the arm) is the most feared complication of dissection. It is rare and depends on the number of nodes affected and removed, but also on the radiotherapy of the armpit. Being overweight and not exercising increases the risk of sequelae of axillary surgery.