A white woman looks for swelling under her arm

Lymphedema happens when lymph fluid builds up in the hand, arm, breast, chest wall, or under the arm on the side where you have breast cancer, resulting in swelling and other possible symptoms. Lymphedema can occur anytime after treatment—even many years later. As fluid builds up and the area swells, it can cause pain, reduced movement, serious infections, emotional upset, and reduced quality of life.

Researchers believe lymphedema is largely unrecognized and underdiagnosed. Studies show that between 5 and 50 percent of women treated for breast cancer develop the condition, depending on the treatment they receive.

Swelling can be lessened with early and proper detection, skilled therapy, and ongoing self-care. Even if swelling goes away, lymphedema is a long-term side effect and remains a health concern for the rest of your life. But with proper treatment, it is possible to manage lymphedema well and move forward with your life.

This page helps you understand the causes of breast cancer-related lymphedema, methods to reduce your risk and to identify lymphedema early, and treatments to manage it.


Causes of lymphedema

Just under the skin, above your muscles, lies the lymphatic system. It’s a series of tiny, thin tubes called vessels that carry a nutrient-rich fluid, called lymph. The vessels travel through a web of lymph nodes — small, round organs that store white blood cells and filter bacteria and waste. Lymph fluid helps the body fight infection and then drains to other parts of your body. The lymph system also removes fluid that leaks out of blood vessels, returning it to the system that handles your heart and blood.

To stay healthy, lymph fluid must keep moving. When lymph nodes are damaged or removed because of breast cancer surgery or radiation, scar tissue can form and keep fluid from draining. At first, the tissue may feel firm and thick, but as fluid backs up, swelling and inflammation set in. If the swelling continues, the protein-filled fluid increases the risk for infection and more swelling.

Breast cancer surgery can cut through the lymphatic channels, breaking up the pathways where lymph travels. The risk for lymphedema after surgery depends on:

  • The type of breast cancer surgery you had
  • The location and number of lymph nodes removed
  • The way your body drains the fluid after surgery
  • The way your body heals afterward

Surgery and lymphedema risk

Surgery in the armpit, or axillary, region removes lower lymph nodes where the breast and underarm tissue meet. Higher lymph nodes in the underarm area may also be removed. Some of the specific risk factors for lymphedema and breast cancer surgery are:

  • An axillary lymph node dissection that removes many nodes in the lower to mid-upper underarm. Having more than 10 lymph nodes removed is a risk factor for developing lymphedema.
  • Sentinel lymph node biopsy that removes only the main nodes to which the breast lymph drains, typically one to three nodes in the lower armpit. Lymphedema can develop after sentinel node biopsy, but it happens at a lower rate than with an axillary dissection.
  • If you had both breasts removed in a bilateral mastectomy, your risk is on the side or sides where lymph nodes were taken.

Radiation therapy and lymphedema risk

Radiation therapy can also increase the risk for developing lymphedema in several ways:

  • With scarring, or fibrosis, that prevents lymph flow.
  • The wider the area of the breast radiated and the more of the underarm the radiation reaches, the greater the lymphedema risk.
  • Postmastectomy radiation, radiation to the chest wall after the breast is removed or reconstructed, can lead to lymphedema, especially if the lymph node area also is radiated.

Other risks factors for lymphedema

We do not know why one person gets lymphedema after breast cancer treatment while another, who has the same treatment, does not. Genes may play a role. You should discuss your concerns with your healthcare team. Worry about the risk of lymphedema should not keep you from getting the breast cancer treatment that is best for you.

Additional factors that influence the risk of developing lymphedema are:

  • Having multiple lymph nodes with cancer
  • Getting an infection on the side of your body that had surgery
  • Overuse or trauma to the hand or arm on the affected side
  • Being a younger age at cancer diagnosis
  • Being overweight or obese
  • Gaining weight after treatment
  • Certain chemotherapy treatments, such as the taxanes

Preventing lymphedema

If breast cancer surgery or radiation involved your lymph nodes, there is no sure way to prevent lymphedema. But you can lower your risk or lessen the severity of lymphedema by paying attention to changes on your treated side, following a few precautions, and getting medical help quickly if signs occur. Here are some ways to help prevent lymphedema:

  • Avoid injury. On the side where you had lymph nodes removed or had radiation treatment, do not get vaccines, injections, acupuncture, blood draws, or blood pressure tests. Consider wearing a lymphedema bracelet on the affected side to alert providers. If you had treatment on both sides, choose the side that had fewer lymph nodes removed or was treated longest ago. In some cases, your leg may be used for these procedures.
  • Clean cuts and scrapes quickly. Apply a topical antibiotic to avoid infection. If you get an infection, treat it immediately. Call your doctor if you have an infection and get a fever or feel cold, see redness or swelling, or feel heat near a scrape, cut, burn, or injury.
  • Keep your weight down. Extra pounds increase your risk. If you have lymphedema, losing weight may help reduce symptoms.
  • Use care during travel. The lymphatic system is sensitive to decreased cabin pressure and high altitudes. If you have lymphedema, wear a compression sleeve, garment, or bandages when you fly. To control swelling, use a compression glove and squeeze a rubber ball to stimulate lymph flow. Consider carrying an antibiotic with you. If you do not have lymphedema, your provider can tell you whether to wear special garments when you fly.
  • Prevent sunburn. Use SPF15 or greater sunscreen, with UVA and UVB protection.
  • Spray bug repellent to prevent bites.
  • Keep your skin moist. Using a nutrient-rich lotion will nourish and protect your skin.
  • Dress comfortably. Avoid tight rings, watches, bracelets, clothes, sleeves, and cuffs. Try to avoid carrying heavy purses, bags, or groceries on your treated side.
  • Stay away from extreme cold and heat. If you want to use a hot tub or sauna, the National Lymphedema Network suggests you limit use to no more than 15 minutes. Keep the affected area out of the hot tub.
  • Care for your nails. To avoid cuts that could become infected, gently push back your cuticles with a towel after showering. Do not cut them. Acrylic nails might cause infections.
  • Exercise. Research shows exercise may help prevent lymphedema. After surgery, make sure you begin exercising slowly and increase your effort gradually. Physical therapists and other providers can show you how to exercise to protect your lymph system. If you have lymphedema, wear bandages or a compression garment during exercise. Watch for pain and swelling.
  • Protect your hands, fingers, and arms. Use an oven mitt for cooking and baking, and keep your affected arm away from steam. Wear gloves to garden, clean, and do house repairs. An electric razor helps avoid nicks —   which can become infected — to your underarms.

Video: Nadiyah’s story: Moving beyond lymphedema

Discover Nadiyah's journey of staying active with lymphedema, spinal stenosis, and sciatica after a breast cancer diagnosis when she was 29 years old.


Early warning signs of lymphedema

Right after breast cancer surgery or radiation, you may have swelling, called edema. This is not the same as lymphedema. But if swelling persists for 3 to 6 months, get a lymphedema evaluation.

It’s important to seek medical advice from your healthcare team as soon you can at the first sign or symptom of lymphedema. The condition may develop slowly over time or more suddenly if you have an injury or infection in your arm. Early diagnosis and getting treatment started quickly has shown to greatly improve lymphedema outcomes. Some signs to look for:

  • You might notice changes in how your skin feels or moves before anyone else sees swelling, including your provider. Speak up about any change you feel.
  • Before swelling can be seen, you may feel an achiness, heaviness, tingling, or increased warmth in your limb or hand. Monitor the tissue texture and skin on the side where you had surgery or radiation. Ask:
    • Are the veins or tendons on one hand harder to see than they used to be?
    • Can you see valleys between your knuckles?
    • Do your clothes or jewelry fit tighter on the side of the cancer?
  • Swelling might occur during the day and go away at night or start and then go away when you elevate the swollen area. Follow up with your provider if these signs persist.

Diagnosing lymphedema

Measuring the arm helps detect lymphedema. If possible, have the circumference of (the distance around) your arms measured before surgery or radiation to get a baseline reading. Some facilities take baseline measurements before treatment and measure your arms regularly afterward. If there is a change in size, you can start treatment quickly. Some techniques used to measure the volume and size of your arm include:

  • Circumference measurements using a tape measure to look for swelling in the arm. This is the most common method. Your provider will measure your arms from your hand to the armpit at different places. These places will be the same every time your arms are measured.
    • Any change in circumference of more than 2 centimeters, at any place in the affected arm, may suggest lymphedema.
  • Bioimpedance passes low-dose electricity through the arm to see if you have extra fluid on the side where you had cancer. The electricity is about the same as you would get during an EKG. For this test, a provider places electrodes on each wrist and your right foot. Cables are attached to each site for a few minutes. The test does not hurt. The resistance to the electricity will be different on the affected side if you have lymphedema.
    • This test is available to people who do not have implanted metal, such as a pacemaker or defibrillator.
  • Perometry passes infrared signals through your arm to measure the volume of fluid. This method uses a machine called a perometer. You will sit or stand beside it and stretch your arm over a table as a square frame passes over your arm. After measuring both arms, the perometer compares the volume of fluid in milliliters between your two arms.
    • This test is best given before lymph node surgery and every 3 months after. It is available at limited facilities and through research studies.
  • Volumeter, or water displacement, is rarely used.

Some doctors use special x-rays to see lymph flow to diagnose lymphedema. Others look at the area on a CT or MRI scan.

If you already started treatment, it helps to see a lymphedema therapist to talk about your personal risk. If you have questions about how to measure your arm on your own, ask your oncologist or oncology nurse. When you see any signs or symptoms of lymphedema, contact your providers as soon as possible.


Finding help for lymphedema

It is important to see a special therapist who can reduce the swelling and other lymphedema symptoms as well as teach you ongoing care. Your cancer care team can make a recommendation. Some things to know:

  • The Lymphology Association of North America (LANA) certifies therapists in complete decongestive therapy using national standards. Therapists may also be certified by the program that trained them. Your healthcare provider also may have suggestions.
  • Certified providers are often physical therapists or occupational therapists (OTs), as well as nurses, doctors, or massage therapists. When choosing lymphedema therapists, ask about their training.
  • Insurance coverage of lymphedema treatment can vary. Be sure to verify whether their services are reimbursed by your health insurance plan.

Learn more on our Lymphedema treatments page.


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Reviewed and updated: July 15, 2019

Reviewed by: Lori B. Ranallo, RN, MSN, CBCN, APRN-BC


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