The axillary (underarm) lymph nodes may become enlarged or swollen any time they produce additional white blood cells to ward off an infection. These infections are often benign (non-cancerous). For example, lymph nodes may swell from the formation of an abscess (closed pocket filled with pus) in the nodes. However, lymph nodes may also swell if they contain cancer cells.
Unfortunately, there is no perfect way of determining whether a lymph node is enlarged because it contains cancerous cells or if it is enlarged due to other, non-cancerous causes unless a biopsy is performed. However, there can be some indications from examination that a lymph node is more likely to be benign. For example, if a lymph node is less than one centimeter in diameter and soft, rubbery and tender, it is more likely to have swollen due to a benign cause, such as recently shaving under the arm, using a new deodorant, having a manicure, or slightly injuring the skin on the side of surgery (called the ipsilateral side).
Because of a higher risk of lymph node infection and inflammation, surgeons usually recommend that a patient avoid having blood drawn, blood pressure measurements taken, or perform unprotected work with the hand/arm on the side of surgery since these activities have been shown to increase the chances of lymphedema (chronic swelling) of the arm.
Many physicians feel that in a patient who has been diagnosed with breast cancer, it is usually wise to be cautious and biopsy any enlarged lymph nodes if the swollen node persists for beyond a month or two since it may contain cancerous cells. It is important for patient and physicians to work out a plan regarding how long a lymph node should persist before it must be removed. In some instances, the enlarged node may be sampled by an ultrasound-guided needle biopsy. However, there may be a higher risk of missing cancer cells if a needle biopsy is performed rather than surgically removing the entire node. Learn more about breast biopsy.
It is important that a patient ask her physician when it is safe to begin exercising and using the surgery-side arm again after a mastectomy. While there are no contraindications to performing any number of exercises after full recovery from mastectomy, there are certain precautions that should be taken by any person who has undergone a mastectomy, especially those who have had accompanying lymph node dissection.
Any minor injury to the skin on the side of the mastectomy may become infected more easily than an injury on the other arm. This is because the lymphatics have been disrupted and lymph nodes have been removed, leaving the arm more vulnerable to invading organisms such as bacteria. The lymphatics normally serve to drain fluids from the limb and the lymph nodes act, in some sense, as a filter, removing harmful substances from the lymph fluid.
Up to 20% of women who have undergone mastectomy and axillary lymph node dissection experience some edema (swelling) in the arm and report a higher incidence of irritation to minor skin trauma for this reason. Click here for more information on lymph nodes and breast health.
In addition, there may be a higher chance of axillary vein thrombosis (a clot in the deep vein in the armpit) in women who have undergone surgery in that area; especially if a more complete axillary dissection with the removal of 30 or more lymph nodes is performed. This is because the lymph nodes are normally located near blood vessels, and (unavoidable) scarring at or near the axillary vein may result from surgery. This scarring may tether, kink, or narrow the blood vessel and make it more susceptible to further injury.
While an increased incidence of deep vein thrombosis has not been reported in the medical literature after axillary surgery, it has been, in rare cases, associated with strenuous upper body exercise, since overdeveloped musculature may affect nearby nerves, veins, and arteries (thoracic outlet syndrome). Therefore, many physicians recommend tempering upper extremity exercise after surgery with periods of rest and keeping the arm elevated above the level of the heart for a few hours, to avoid undue swelling. Mastectomy patients should be careful not to exercise too intensely in order to avoid preventable injury.
On a positive note, regular use of the muscles after mastectomy will keep joints limber, stretch and soften scar tissue, help recruit (open up) new lymphatics, and promote blood flow and actually help reduce clot formation. These benefits generally outweigh the risks of a careful exercise program after mastectomy.
- The National Cancer Institute provides information on breast cancer and lymph nodes.
- Learn more about breast cancer staging and survival rates.
- Learn more about axillary node dissection.
- Learn more about sentinel node biopsy.
- Learn more about lymphedema.
