Lymphedema is a chronic lymphatic condition that occurs when lymph fluid accumulates just below the skin surface, causing disfiguring swelling or edema. While the edema is most commonly seen in the arms or legs, it can affect other body parts too. For example, the abdomen, armpit, back, breast, chest, face, genitals, head, neck, or pelvic area can also take a hit.1 2
What Causes Lymphedema?
Your lymphatic system includes lymph fluid, lymph nodes, lymph vessels, and lymphoid tissues. The lymph vessels transport the protein-rich lymph fluid between the body tissues and the bloodstream. The lymph nodes, in turn, filter the fluid before releasing it into the bloodstream. You’ll also find the lymphocytes in the lymph nodes. These white blood cells play a very important part in the immune system, helping fight viruses and bacteria. If obstructed for some reason, the nodes cannot keep up with the fluid load and filtration efficiency falls. This results in fluid buildup in the soft tissues, causing lymphedema. Lymphedema also develops when the lymph vessels are damaged and cannot flush out waste filtered by the lymph nodes.3 4 Lymphedema is usually of two types: primary or secondary lymphedema.
Primary Lymphedema: Causes
Primary lymphedema is a rare hereditary condition that occurs when there are congenital abnormalities in the lymphatic system. It can affect a single or multiple parts of the body. The cause of primary lymphedema is still largely unexplained although researchers do believe that it happens because of changes or mutations in one of the disease genes.
Primary lymphedema in babies and children could be associated with other abnormalities in the system and would need to be treated accordingly. For example, lymphedema is one of the conditions that affect individuals with Milroy disease, aside from other genetic conditions such as Park-Weber Syndrome or Klippel-Trenaury Syndrome and abnormalities such as lymphangioma or hemangioma.
Primary lymphedema could rear its head in puberty too. Lymphedema praecox or Meige disease is the most common type of lymphedema that appears during puberty, and it mostly affects girls. It usually shows up in both the legs from hip to toes.
Secondary Lymphedema: Causes
Secondary lymphedema occurs because of damage to the lymphatic system. Infection, inflammation, cancer-related radiation and surgery, venous diseases, obesity, immobility, or trauma are common causes of secondary lymphedema. In cases of lymphedema because of cancer treatment, most cases develop within the first 6–18 months of treatment, although some cases could develop many years later too.7
Risk Factors For Secondary Lymphedema
Lymph node surgery and radiation therapy are considered to be the greatest risk factors for lymphedema. However, there are other risk factors too that decide how high or low your risk is for secondary lymphedema.
Removal Of Several Lymph Nodes
If you’ve had lymph nodes removed for cancer treatment, it increases the risk of lymphedema. For example, surgeries that may require lymph node removal due to cancer in the head and neck area, breast, cervix, colon, bladder, prostate, skin, or testicles. While surgeons try their best to minimize damage to the lymphatic system, it is not always possible.8 This is because the risks of cancer far outweigh the risks of lymphedema.
Removing lymph nodes also increases the risk of infections post surgery, and these infections are another prominent risk factor for lymphedema.9
Multiple Surgeries Or Extensive Surgery
If lymphatic pathways are disrupted because of any trauma or multiple surgeries (even non-cancerous), it can result in lymphatic impairment and lead to lymphedema. For example, mastectomy and breast reconstruction are both extensive surgeries associated with an increased risk for lymphedema.10 Fortunately, the risk of developing lymphedema after breast cancer surgery is slowly decreasing. From a steep 50 percent chance in earlier times, the risk has dropped to 15–25 percent today.11
In cases of breast cancer or any other form of cancer that requires radiation therapy to treat cancerous cells, the risk of permanent damage to the lymphatic system is quite high. Healthy lymph nodes and vessels could also be damaged during radiation therapy. Lymphedema is a natural consequence of this damage.12
Radiation therapy can also cause scarring of the lymphatic vessels, which is a forerunner of fibrosis. This is a condition that involves excessive formation of fibrous connective tissue, leading to scarring and thickening of the affected tissue. Fibrosis further decreases lymphatic flow and increases the risk for lymphedema.13 Closely monitor radiated area for discoloration, redness, and blisters and let your doctor know right away if there are any changes.14
While chemotherapy by itself may not lead to lymphedema, it could lead to weight gain, which is a risk factor for lymphedema. If shoulder/axillary lymph node dissection was done for breast cancer treatment, you may be asked to avoid injections, chemotherapy, or drawing of blood on the arm on the treated side.15
There are instances of lymphedema in persons with medical conditions that affect the flow of venous blood. The diseased veins cannot handle the fluid volume and, as a result, fluid overflows into the tissue spaces. This in turn exhausts the lymphatic system in the area and causing lymphedema. Two such venous diseases include varicose veins and deep vein thrombosis (DVT).16
Being Overweight Or Obese
Being overweight is defined as having a body mass index (BMI) of 30 or greater. And those who are obese carry a greater risk of developing lymphedema after being treated for cancer. When the body has extra fat, the fat tissue needs more blood vessels to bring it oxygen and nutrients. As a result, these tissues have more fluid to get rid of too. If the amount of fluid coming out cannot be handled by the lymphatic system, it could lead to lymphedema.17
Infection Or Injury On Treated Side
- Any injury or infection on the side of the body that was treated for cancer increases the risk for lymphedema. Injury and infection lead to inflammation. This in turn translates to increased blood flow to that area, resulting in higher output of fluid. If the lymphatic system cannot manage the fluid load, it triggers lymphedema.
- Venipuncture, or the process of piercing a vein to draw blood, increases the risk of developing secondary lymphedema too. Avoid any needle punctures on the arm or leg on the side of the body treated for cancer. That would include blood draws, catheter fitments, injections, and even chemotherapy.
- Fibrosis can lead to infections such as lymphangitis or cellulitis, both of which are triggers for lymphedema. This is because tissue damage does not allow oxygen and essential nutrients to reach the area in a timely manner, leading to delays in wound healing. This provides bacteria a perfect medium to grow and cause infections. So, if you are suffering from either of these, take care of your skin meticulously and avoid injections and/or blood draws.18
Parasitic infections such as lymphatic filariasis, also known as elephantitis, can result in obstruction of the lymphatic channels and result in lymphedema. Thread-like microscopic worms thrive in the human lymphatic system, causing severe damage. The worm is transmitted through mosquito bites, making parasitic infections a common cause of lymphedema in mosquito-prone regions.19
Conditions such as rheumatoid arthritis (RA) and eczema cause tissue to become swollen and red. In severe cases, the chances of damage to the lymphatic system are quite high.20
Lack Of Movement
People with limited mobility because of illness, arthritis, or nerve damage may be at risk of developing lymphedema too. Exercise and movement help with lymph drainage since the muscle activity around the lymph vessels keep them sufficiently stimulated. Limited movement makes the muscles inactive, resulting in fluid accumulation and, subsequently, lymphedema.21
|↑1||What lymphoedema is. Cancer Research UK.|
|↑2, ↑4, ↑5||Lymphedema. Society for Vascular Surgery.|
|↑3||What Is The Lymphatic System?. National Lymphedema Network.|
|↑6||Hereditary Lymphedema. National Organization for Rare Disorders (NORD).|
|↑7, ↑9, ↑10, ↑15, ↑17||Lymphedema Risk Factors. Breastcancer.org.|
|↑8, ↑12, ↑16, ↑19, ↑20, ↑21||Causes of lymphoedema. NHS Choices.|
|↑11||FAQS ABOUT LYMPHEDEMA. Lymphatic Education & Research Network.|
|↑13, ↑14, ↑18||What Causes Lymphedema?. National Lymphedema Network.|