Breast cancer surgery requires the removal of some or all lymph nodes from the armpit (axilla). The axilla contains around 15-30 lymph nodes and this number can vary between individuals.
Approximately 30-35% of breast cancer patients will have cancer spread (metastasis) to the axillary lymph nodes. Removal of these cancerous nodes provides adequate treatment to the axilla and is also important to identify patients that may require other treatment such as radiation and chemotherapy.
Lymph node surgery for breast cancer has undergone a major revolution. Previously patients routinely underwent a complete axillary lymph node clearance (removal of all the lymph nodes from the armpit). This resulted in many unnecessary operations and complications for patients that did not have axillary lymph node metastases (spread of breast cancer cells to the axilla).
The aim of lymph node surgery is to remove the smallest number of nodes necessary to prove cancer spread and to avoid the complications of surgery. However to determine which patients have cancer-spread to their lymph nodes can only be reliably done with a surgical biopsy.
With the advent of ‘sentinel lymph node surgery’, this has resulted in fewer unnecessary axilllary node clearance operations. This procedure involves the selective removal of the ‘sentinel nodes’ that the tumour cells can potentially first spread to. These nodes are marked by a pre-operative mapping procedure (lymphoscintigraphy) at a nuclear medicine centre. Although this procedure identifies the ‘sentinel nodes’ it does not tell us if they are involved with cancer cells. Hence a surgical biopsy (removal) of the sentinel lymph node is essential.
Sentinel node mapping allows for the removal of the smallest number of lymph nodes and reduction in the complications of axillary surgery. If the axillary lymph nodes demonstrate a large degree of cancer-spread, then a complete axillary node clearance may be recommended.
Sentinel node biopsy (SNB):
The aim of SNB is to remove lymph nodes (usually 1-3) from the axilla (armpit). The sentinel nodes are the first lymph nodes to which breast cancer cells can potentially spread. In the vast majority of patients these lymph nodes are located in the axillary. However occasionally these lymph nodes are located outside of the axilla such as the internal mammary lymph nodes (see below).
Sentinel lymph node identification may not always be accurate at predicting cancer spread to the lymph nodes. Other nodes maybe abnormal at the time of surgery and these nodes are also removed. Hence the total number of nodes removed range from 1-5. The operation is usually associated with discomfort to the upper arm for a few days. Some women are aware of one or two fine cord-like thickenings in the armpit after the operation. This can be a bit tender but will usually settle after 2 or 3 weeks.
If the lymph nodes have cancer cells within them (known as positive sentinel nodes) then the rest of the lymph nodes in the axilla may need to be removed. This is an operation called axillary lymph node clearance. If the sentinel nodes are not positive then no further surgery is needed.
How are the sentinel nodes found?
There are two ways of finding the sentinel nodes. The first is using radioactivity and this is procedure is called a lymphoscintogram. This procedure is performed at a nuclear medicine centre and involves the injection of radioactive substance into the breast around the tumour. The lymphoscintogram is done either on the day of surgery or the afternoon before. Be prepared to spend a few hours at the nuclear medicine centre as it can take some time for the radioactive substance to travel to the lymph nodes.
The second method is using intra-operative injection of blue dye. Under anaesthesia Dr Noushi will inject blue dye into the breast around your tumour. This makes the sentinel lymph nodes appear blue and therefore easier to identify. Dr Noushi usually uses both lymphoscintography and blue dye because together they identify sentinel nodes more accurately, but in some cases only one of the two methods may be used.
What are internal mammary sentinel nodes?
Sometimes a sentinel node can be found near the sternum (breast bone) and these nodes are called internal mammary sentinel nodes. When radioactive dye drainage from the breast injection travels to these nodes it will clearly be identified by the nuclear medicine scans and marked with “X” on the skin overlying the lymph nodes.
Dr Noushi routinely biopsies sentinel nodes that are located outside of the axilla such as the internal mammary lymph nodes. Cancer spread to these nodes such as the internal mammary lymph nodes are important to identify as it does influence adjuvant treatment such as radiotherapy.
Internal mammary sentinel node biopsies do cause a little more discomfort after the operation and are associated with more risks than the sentinel node biopsy in the armpit. These risks are rare but they include the risk of bleeding into the chest or injuring the lung. Very rarely does the chest need to be opened to control any internal bleeding and a chest tube may be inserted for a couple of days.
What happens if the sentinel node is Positive?
Dr Noushi occasionally arranges for a “frozen section” on the sentinel nodes that have been removed only if you are undergoing a mastectomy. Frozen section is an immediate one-cut analysis of these nodes by the pathologist while you are under anaesthesia, which takes approximately half an hour. If the frozen section demonstrates a large cancer spread to the lymph node then Dr Noushi can perform an axillary clearance of all the lymph nodes, which would ordinarily be recommended for patients who undergo a mastectomy. Hence avoiding a second operation.
Sometimes the frozen section analysis will be negative, however upon a complete pathological analysis of the entire lymph node (multiple cuts of the lymph nodes), this can occasionally show cancer cells that was not identified during the frozen section analysis. This complete pathological analysis can take up to 1 week.
If the SNB are positive (cancer spread within them) you may require a second operation at a later stage to perform an axillary clearance. However the pathology will be discussed at a multidisciplinary breast oncology meeting and the decision made at that stage. Axillary clearance is not usually required if there is only small degree of cancer spread to the axillary lymph nodes and other cancer treatment is planned. This will be decided at the multidisciplinary breast oncology meeting.
Axillary node clearance:
This operation involves removing all lymph nodes from the armpit (axilla). It is performed when there is definite spread of breast cancer to these nodes. A drain is left in the wound after this operation and may occasionally be left in for up to two week.
The main effects of this operation are that your shoulder is quite stiff for the first few days. A near full range of movement can be expected after 2-4 weeks with regular shoulder exercises, which you will be taught. Some women experience an area of numbness in the upper arm area that can be permanent but often improves with time. Approximately 10 - 15% of women develop a swelling in the arm that can be permanent but may improve with appropriate treatment.
Surgery and Aftercare:
The length of the operation and duration of hospital stay depends on the extent of breast and lymph node surgery undertaken. For most patients this operation takes an additional 0.5-1 hour. Often the lymph nodes are removed through the breast incision, however if a complete axillary clearance is performed then there will be a separate skin incision in the axilla. Dissolving stitches are used and there will be a waterproof dressing over your wound. You can shower with the dressing on, however ensure you do not rub or soak it. This dressing can be removed in 1 week.
If you have a complete axillary clearance because your sentinel node is positive then you will need to stay in hospital for 2-3 nights. In addition a pastic tube called a drain will be placed at the time of surgery and tunnelled away from the wound. This is left in for between 2 and 10 days. This drain removes any residual blood and fluid that the body produces after an operation. You can move around while you have the drain in with the aid of a small bag to avoid pulling on it. Most patients will stay in hospital for 2-3 nights and can any go home with the drain. Nursing staff from APAC will visit you in the home and help you care for the drain. They will also remove it for you according to Dr Noushi’s instructions. Occasionally, fluid collects in the wound (seroma) even after the drain has been removed and this is drained at the clinic, painlessly.
Shoulder exercises will begin on the first day after surgery and gradually become more extensive over the following few days. It would be normal for most women to regain a full range of movement of the shoulder within 6 weeks of this operation.
What will the scar be like?
If a mastectomy is being performed then the lymph node surgery will be performed through the mastectomy incision. However If you are having breast conserving surgery then the scar may be separate from the breast scar, but is placed within the skin creases under the armpit. This usually heals as a faint white line. Occasionally a sentinel node can be found near the sternum (breast bone) instead of the armpit and a separate cut may be needed for that.
What happens if my arm becomes swollen after lymph node surgery?
If this occurs then early treatment is important. You will be taught how to massage the arm and encouraged to apply moisturiser to it. If it is uncomfortable, a compression sleeve will be fitted. Treatment is aimed at controlling and reducing the swelling.
As with all surgical procedures axillary surgery does have some risk. Serious complications after surgery are rare. It is not usual to outline every possible and rare complication from an operation, however it is important that you have enough information to make an informed decision.
Any operation can be complicated by infection, bleeding, seroma and wound healing problems. Wound healing can be particularly affected by infection and smoking. Any operation can be associated with anaesthetic problems (nausea in particular), venous thrombosis and allergic reaction to drugs or dressings. Every effort is made to avoid these problems.
Some problems from axillary surgery include (but not limited to) the following. The complications from sentinel node biopsy are similar but far less frequent than that of a complete axillary node clearance.
Bleeding - All visible bleeding is stopped during the operation, but sometimes blood vessels can reopen and bleeding can restart. A bit of bruising is common and is nothing to worry about. A lot of bleeding causing a lump underneath the wound may require another operation to find and stop the bleeding vessel.
Seroma - This is fluid made by the body that collects under the wound. It produces a swelling and sometimes some tightness. This is easily treated by removing the fluid with a needle and syringe in a relatively painless procedure. Some patients need this drained more than a couple of times, but this is not an important problem and usually settles within a few weeks of surgery.
Infection - Any operation site can become infected. This occurs in less than 0.5% of patients. If it were to occur then it will usually happen in the first week after surgery. The wound becomes red, swollen and tender, and there may be a discharge through the wound. It is usually treated with antibiotics alone, but sometimes the wound has to be re-opened to allow the discharge to drain.
Blue dye - If blue dye is used in the procedure, when you wake up you may look slightly blue all over. You may pass blue-green urine and stools for 1-2 days. In addition, the area of skin where the dye was injected often appears blue and sometimes takes several weeks to clear. An allergic reaction to blue dye is a very rare complication. Fortunately blue dye is injected when you are asleep and the anaesthetist will be monitoring you closely. Occasionally the operation may not proceed if you have a severe allergic reaction.
Scarring - Occasionally one can develop scarring in the armpit that usually settles with massage therapy and time. Very rarely scarring can be long-standing and cause shoulder/ arm stiffness.
Shoulder and arm stiffness - This is a common problem that usually resolves quickly. The breast nurses will give you exercises to do after the operation, which can help prevent this. About 4% of patients have long-term trouble with stiffness.
Lymphoedema - This is swelling of the arm or breast that occurs because the lymph flow has been disrupted. It is more frequenty troublesome in patients undergoing axillary node clearance (~10-15% of patients). It can be managed by bandaging and massage therapy. The breast nurses will tell you how to care for your arm after to avoid this problem.
Pain - Most patients have some pain in the armpit after this surgery however it usually subsides in a few days. Very rarely the pain is severe and this will require further attention – it may indicate an infection, bleeding or seroma collection. On rare occasions the pain becomes chronic and will require ongoing massage therapy and medication.
Altered sensation and nerve injury - There are several skin nerves, which supply sensation to the skin in the armpit and upper arm. These nerves are located in the area where the lymph nodes are removed. Every effort is made to avoid damage to these nerves. However occasionally the nodes are adherent to these nerves and they are either bruised or divided. If this occurs you may experience some numbness to the inner aspect of your arm, and occasionally some shooting pains. This usually settles with time and does not require any treatment. Very rarely the nerves that supply the muscles of the shoulder and arm movements are injured. They are generally well protected during surgery.