Axillary dissection is removal of the majority of the lymph nodes from the armpit. It is done upfront in patients who are known to have cancer in the lymph nodes, but also as a second procedure in patients with a positive sentinel lymph node. By knowing how many positive lymph nodes there are, it gives Dr Adams and her team information about your prognosis. This helps determine the need for other treatments after surgery such as radiotherapy and chemotherapy. It also removes the cancerous nodes which can reduce the risk of progression or recurrence of the cancer.

Through a cut under the armpit (or through an existing mastectomy scar) the lymph nodes are separated from the surrounding important structures and removed. There is not a set number of lymph nodes removed, all the nodes between set anatomical boundaries are removed. This number varies very much from person to person, but commonly is between five and thirty-five. A standard axillary dissection for breast cancer removes two of the three lymph node groups from the armpit, which leaves you with a handful of nodes at the top.

Axillary dissection is a safe surgery, but there are some uncommon risks. The disruption of the lymphatic channels can slow the flow of the lymphatic fluid from the arm which can result in swelling of the arm or lymphoedema. The lymphatic fluid can accumulate in the armpit after the surgery for a short while and is known as a seroma. In the early post surgery period this is prevented with a drain, but after drain removal patients may need to have the fluid drained away. Eventually, the lymphatic channels find a detour around where the surgery was done and this problem goes away. Damage to nerves in the armpit is another risk of surgery. These are most commonly sensory nerves, which leaves a numb patch on the side of the chest or the upper inner arm. There is a risk of damage to other nerves which can cause minor weakness at the shoulder, though this is extremely rare.