Edema vs. Lymphedema in Cancer

Edema and lymphedema both mean swelling, but they are not the same thing. Edema is a broad term for fluid trapped in body tissue. Lymphedema is a specific kind of swelling. It happens when your lymph system, which normally drains fluid, is damaged or blocked.

Peripheral edema means fluid in the arms, legs, feet, or hands. NCI says chemotherapy, some hormone therapy, immunotherapy, and targeted therapy can all cause it. Some medicines do too, such as steroids, blood pressure pills, and NSAIDs like ibuprofen. Heart, kidney, liver, and thyroid conditions can cause it as well. Swelling from cancer treatment is usually mild. It often goes away after treatment ends.

Lymphedema is different. It happens when cancer or its treatment blocks the flow of lymph fluid. That can be a tumor pressing on the flow, surgery that removes lymph nodes, or radiation that leaves scar tissue. Unlike ordinary edema, lymphedema does not just clear up with rest. It can start soon after treatment, or years later. NCI says it usually develops slowly, over months or years. It cannot be cured, but treatment can reduce the swelling and help you function.

Track where the swelling is. Lymphedema often shows up near where you had surgery or radiation. It may make one arm or leg look bigger than the other. It often brings a heavy, full, or tight feeling, and sometimes numbness or tingling.

Peripheral edema is more likely to affect both legs or feet. Skin may look puffy or shiny, or stay dented for a moment after you press it. It can also shift with position, easing overnight when you raise your legs.

These clues help, but they do not settle it. NCI advises telling your doctor about swelling that does not go away, so the cause can be found and treated early.

Lymphedema needs its own care plan. It often includes compression garments, gentle massage that moves lymph fluid, and specific exercises. A certified lymphedema therapist can build a plan that fits your situation. Starting early makes lymphedema easier to control.

Protecting the skin in the swollen area matters too. Swollen skin is stretched thin, so bacteria get in more easily. That raises the risk of cellulitis, a skin infection that can become life-threatening if it is not treated.

• Call 911 or go to an emergency department if you are short of breath, have sudden pain with swelling, the swelling is moving up an arm or leg, a swollen area turns painful and warm, you gain weight rapidly, or you cannot empty your bladder. NCI lists these as reasons to seek emergency care for swelling.
• Call 911 or go to an emergency department if swelling in your face, neck, or throat makes it hard to speak, swallow, or breathe. That is an airway problem and cannot wait for a callback.
• Ring your cancer team without delay, day or night, if you have a temperature of 100.4°F (38°C) or higher during chemotherapy. CDC treats fever on chemotherapy as a medical emergency, all the more so with a red, hot, tender area that may be cellulitis. If you cannot get through soon, go to an emergency department and tell them you are having chemotherapy.
• Call your care team the same day if a swollen area is red, tender, or warm without any fever. Cellulitis needs antibiotics started quickly.
• Call your care team within a day or two if you notice new swelling, or a heavy, tight, or full feeling in an arm, leg, or the area where you had surgery or radiation.

• Does my swelling fit the pattern of edema, lymphedema, or something else?
• Am I at risk for lymphedema based on my surgery or radiation?
• Should I see a certified lymphedema therapist?
• What early signs of infection should I watch for in that area?
• What self-care is safe for me to try now?

• National Cancer Institute — Edema (Swelling) and Cancer Treatment
• National Cancer Institute — Lymphedema and Cancer Treatment
• MedlinePlus — Lymphedema
• CDC — Fever During Chemotherapy Is an Emergency