Lymphedema After Breast Cancer: Signs, Treatment and Coverage
October 20, 2026 · Breast Cancer, Cancer Survivorship
Lymphedema is swelling caused by a buildup of lymph fluid. After breast cancer, it most often affects the arm or hand on the side that was treated, though it can also affect the breast, chest or back. It can start soon after treatment or years later, and while it usually can't be cured, it can be managed well, especially when it's caught early.
Here's who is at risk, the early signs to watch for, how it's treated, and what Medicare now covers.
Why it happens
The lymph system is a network of vessels and nodes that carries fluid and helps fight infection. Breast cancer surgery often removes lymph nodes from under the arm, and radiation can scar the area. Either can slow the flow of lymph fluid out of the arm, so it builds up and causes swelling.
Who is at risk
Risk depends mostly on how many lymph nodes were treated. The American Cancer Society estimates the long-term risk at about 5% to 17% after a sentinel lymph node biopsy, which removes only a few nodes, and about 20% to 30% after an axillary lymph node dissection, which removes more. Radiation to the lymph nodes and higher body weight raise the risk further. Our guide to breast cancer surgery choices explains the two kinds of lymph node surgery.
Early signs
The National Cancer Institute notes that lymphedema often develops slowly, over months or years. Watch for:
- a heavy, full or tight feeling in your arm, hand, breast or chest
- rings, watches, bracelets or sleeves that feel tighter than usual
- swelling that leaves a dent when you press on it
- aching, tingling or less flexibility in your hand, wrist or shoulder
- skin that feels thicker or harder
Tell your doctor as soon as you notice any of these. Lymphedema is easier to control when treatment starts early. Some cancer centers measure the arm before and after treatment so small changes can be caught.
Get medical care right away if the arm becomes red, warm or painful, or you have a fever. These can be signs of an infection called cellulitis, which needs prompt treatment.
How it's treated
The main treatment is complete decongestive therapy, usually given by a certified lymphedema therapist, often a specially trained physical or occupational therapist. It combines:
- Manual lymph drainage, a gentle form of massage that moves fluid out of the swollen area
- Compression, with bandages at first and then fitted compression sleeves and gloves
- Exercises that help the muscles pump lymph fluid
- Skin care to prevent infection
After the swelling goes down, most people keep it under control at home with compression garments, exercise and self-massage. For some people, compression pumps or surgery to reroute lymph flow are options. You can search for physical therapists in our directory; ask whether they have lymphedema certification, often shown as CLT.
Exercise is safe and helps
People used to be told to protect the arm by not using it. That advice has changed. Research has shown that gradually building up exercise, including weight training, is safe for women at risk of or living with lymphedema and does not make it worse. Start slowly, ideally with guidance from a therapist, and ask whether you should wear a compression sleeve while you exercise.
Everyday tips
- Protect the skin on your arm from cuts, scrapes, burns and bug bites; keep it clean and moisturized.
- Wear gloves for gardening and cleaning.
- Avoid tight sleeves and jewelry on the affected side.
- Keep to a healthy weight.
- Ask your doctor whether to avoid blood draws or blood pressure checks on that arm, and whether to wear a compression sleeve on flights.
What insurance covers
Compression garments used to be one of the biggest out-of-pocket costs for people with lymphedema. Under the Lymphedema Treatment Act, since January 1, 2024, Medicare Part B covers doctor-prescribed compression garments and related supplies for lymphedema. Private insurance coverage varies, and some states require it, so check your plan. Lymphedema therapy is often covered as physical or occupational therapy. Under the federal Women's Health and Cancer Rights Act, most health plans that cover mastectomy must also cover treatment of its physical complications, including lymphedema.
The bottom line
Lymphedema is a common, long-term side effect of breast cancer treatment, especially after many lymph nodes are removed. Know the early signs, report them quickly, and ask for a referral to a certified lymphedema therapist. With compression, exercise and good skin care, most people keep it well under control.
This article is for general information and is not medical advice. Talk with your doctor about your own situation.