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Lymphedema (PDQ®)     
Last Modified: 04/01/2009
Patient Version
General Information About Lymphedema

Key Points for This Section


Lymphedema is the build-up of fluid in soft body tissues when the lymph system is damaged or blocked.

Lymphedema occurs when the lymph system is damaged or blocked. Fluid builds up in soft body tissues and causes swelling. It is a common problem that may be caused by cancer and cancer treatment. Lymphedema usually affects an arm or leg, but it can also affect other parts of the body. Lymphedema can cause long-term physical, psychological, and social problems for patients.

The lymph system is a network of lymph vessels, tissues, and organs that carry lymph throughout the body.

The parts of the lymph system that play a direct part in lymphedema include the following:

  • Lymph: A clear fluid that contains lymphocytes (white blood cells) that fight infection and the growth of tumors. Lymph also contains plasma, the watery part of the blood that carries the blood cells.
  • Lymph vessels: A network of thin tubes that helps lymph flow through the body and returns it to the bloodstream.
  • Lymph nodes: Small, bean-shaped structures that filter lymph and store white blood cells that help fight infection and disease. Lymph nodes are located along the network of lymph vessels found throughout the body. Clusters of lymph nodes are found in the underarm, pelvis, neck, abdomen, and groin.

The spleen, thymus, tonsils, and bone marrow are also part of the lymph system but do not play a direct part in lymphedema.

Enlarge
Lymph system; drawing shows the lymph vessels and lymph organs including the lymph nodes, tonsils, thymus, spleen, and bone marrow.  One inset shows the inside structure of a lymph node and the attached lymph vessels with arrows showing how the lymph (clear fluid) moves into and out of the lymph node. Another inset shows a close up of bone marrow with blood cells.
Anatomy of the lymph system, showing the lymph vessels and lymph organs including lymph nodes, tonsils, thymus, spleen, and bone marrow. Lymph (clear fluid) and lymphocytes travel through the lymph vessels and into the lymph nodes where the lymphocytes destroy harmful substances. The lymph enters the blood through a large vein near the heart.

Lymphedema occurs when lymph is not able to flow through the body the way that it should.

When the lymph system is working as it should, lymph flows through the body and is returned to the bloodstream.

  • Fluid and plasma leak out of the capillaries (smallest blood vessels) and flow around body tissues so the cells can take up nutrients and oxygen.
  • Some of this fluid goes back into the bloodstream. The rest of the fluid enters the lymph system through tiny lymph vessels. These lymph vessels pick up the lymph and move it toward the heart. The lymph is slowly moved through larger and larger lymph vessels and passes through lymph nodes where waste is filtered from the lymph.
  • The lymph keeps moving through the lymph system and collects near the neck, then flows into one of two large ducts:
    • The right lymph duct collects lymph from the right arm and the right side of the head and chest.
    • The left lymph duct collects lymph from both legs, the left arm, and the left side of the head and chest.
  • These large ducts empty into veins under the collarbones, which carry the lymph to the heart, where it is returned to the bloodstream.

When part of the lymph system is damaged or blocked, fluid cannot drain from nearby body tissues. Fluid builds up in the tissues and causes swelling.

There are two types of lymphedema.

Lymphedema may be either primary or secondary:

  • Primary lymphedema is caused by the abnormal development of the lymph system. Symptoms may occur at birth or later in life.


  • Secondary lymphedema is caused by damage to the lymph system. The lymph system may be damaged or blocked by infection, injury, cancer, removal of lymph nodes, radiation to the affected area, or scar tissue from radiation therapy or surgery.


This summary is about secondary lymphedema that is caused by cancer or cancer treatment.

Possible signs of lymphedema include swelling of the arms or legs.

Other conditions may cause the same symptoms. A doctor should be consulted if any of the following problems occur:

  • Swelling of an arm or leg, which may include fingers and toes.
  • A full or heavy feeling in an arm or leg.
  • A tight feeling in the skin.
  • Trouble moving a joint in the arm or leg.
  • Thickening of the skin, with or without skin changes such as blisters or warts.
  • A feeling of tightness when wearing clothing, shoes, bracelets, watches, or rings.
  • Itching of the legs or toes.
  • A burning feeling in the legs.
  • Trouble sleeping.
  • Loss of hair.

Daily activities and the ability to work or enjoy hobbies may be affected by lymphedema.

These symptoms may occur very slowly over time or more quickly if there is an infection or injury to the arm or leg.

Cancer and its treatment are risk factors for lymphedema.

Lymphedema can occur after any cancer or treatment that affects the flow of lymph through the lymph nodes, such as removal of lymph nodes. It may develop within days or many years after treatment. Most lymphedema develops within three years of surgery. Risk factors for lymphedema include the following:

  • Removal and/or radiation of lymph nodes in the underarm, groin, pelvis, or neck. The risk of lymphedema increases with the number of lymph nodes affected. There is less risk with the removal of only the sentinel lymph node (the first lymph node to receive lymphatic drainage from a tumor).
  • Being overweight or obese.
  • Slow healing of the skin after surgery.
  • A tumor that affects or blocks the left lymph duct or lymph nodes or vessels in the neck, chest, underarm, pelvis, or abdomen.
  • Scar tissue in the lymph ducts under the collarbones, caused by surgery or radiation therapy.

Lymphedema often occurs in breast cancer patients who had all or part of their breast removed and axillary (underarm) lymph nodes removed. Lymphedema in the legs may occur after surgery for uterine cancer, prostate cancer, lymphoma, or melanoma. It may also occur with vulvar cancer or ovarian cancer.

Tests that examine the lymph system are used to diagnose lymphedema.

It is important to make sure there are no other causes of swelling, such as infection or blood clots. The following tests and procedures may be used to diagnose lymphedema:

  • Physical exam and history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.


  • Lymphoscintigraphy: A procedure used to make pictures (called scintigrams) of the lymph system to check for blockages or anything else that seems unusual. A radioactive substance is injected under the skin, between the first and second fingers or toes of each hand or foot. The substance is taken up by the lymph vessels and detected by a scanner. The scanner makes images of the flow of the substance through the lymph system on a computer screen.


  • MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).


The swollen arm or leg is usually measured and compared to the other arm or leg. Measurements are taken over time to see how well treatment is working.

Stages may be used to describe lymphedema.

  • Stage I: The limb (arm or leg) is swollen and feels heavy. Pressing on the swollen area leaves a pit (dent). This stage of lymphedema may go away without treatment.
  • Stage II: The limb is swollen and feels spongy. A condition called tissue fibrosis may develop and cause the limb to feel hard. Pressing on the swollen area does not leave a pit.
  • Stage III: This is the most advanced stage. The swollen limb may be very large. Treatment can help, but not cure, stage III lymphedema. Stage III lymphedema rarely occurs in breast cancer patients. Stage III is also called lymphostatic elephantiasis.


Glossary Terms

abdomen (AB-doh-men)
The area of the body that contains the pancreas, stomach, intestines, liver, gallbladder, and other organs.
abnormal
Not normal. An abnormal lesion or growth may be cancer, premalignant (likely to become cancer), or benign (not cancer).
axillary (AK-sih-LAYR-ee)
Pertaining to the armpit area, including the lymph nodes that are located there.
blood
A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.
blood vessel
A tube through which the blood circulates in the body. Blood vessels include a network of arteries, arterioles, capillaries, venules, and veins.
bone marrow (bone MAYR-oh)
The soft, sponge-like tissue in the center of most bones. It produces white blood cells, red blood cells, and platelets.
breast (brest)
Glandular organ located on the chest. The breast is made up of connective tissue, fat, and breast tissue that contains the glands that can make milk. Also called mammary gland.
breast cancer (brest KAN-ser)
Cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.
cancer (KAN-ser)
A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.
capillary
The smallest type of blood vessel. A capillary connects an arteriole (small artery) to a venule (small vein) to form a network of blood vessels in almost all parts of the body. The wall of a capillary is thin and leaky, and capillaries are involved in the exchange of fluids and gases between tissues and the blood.
cell (sel)
The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.
clavicle
Collar bone. Also called collarbone.
cure
To heal or restore health; a treatment to restore health.
diagnosis (DY-ug-NOH-sis)
The process of identifying a disease, such as cancer, from its signs and symptoms.
duct (dukt)
In medicine, a tube or vessel of the body through which fluids pass.
fibrosis
The growth of fibrous tissue.
fluid (FLOO-id)
A substance that flows smoothly and takes the shape of its container. Liquids and gases are fluids.
groin
The area where the thigh meets the abdomen.
infection
Invasion and multiplication of germs in the body. Infections can occur in any part of the body and can spread throughout the body. The germs may be bacteria, viruses, yeast, or fungi. They can cause a fever and other problems, depending on where the infection occurs. When the body’s natural defense system is strong, it can often fight the germs and prevent infection. Some cancer treatments can weaken the natural defense system.
injection
Use of a syringe and needle to push fluids or drugs into the body; often called a "shot."
joint (joynt)
In medicine, the place where two or more bones are connected. Examples include the shoulder, elbow, knee, and jaw.
lymph (limf)
The clear fluid that travels through the lymphatic system and carries cells that help fight infections and other diseases. Also called lymphatic fluid.
lymph node (limf node)
A rounded mass of lymphatic tissue that is surrounded by a capsule of connective tissue. Lymph nodes filter lymph (lymphatic fluid), and they store lymphocytes (white blood cells). They are located along lymphatic vessels. Also called lymph gland.
lymph node drainage
The flow of lymph from an area of tissue into a particular lymph node.
lymph vessel (limf ...)
A thin tube that carries lymph (lymphatic fluid) and white blood cells through the lymphatic system. Also called lymphatic vessel.
lymphatic system (lim-FA-tik SIS-tem)
The tissues and organs that produce, store, and carry white blood cells that fight infections and other diseases. This system includes the bone marrow, spleen, thymus, lymph nodes, and lymphatic vessels (a network of thin tubes that carry lymph and white blood cells). Lymphatic vessels branch, like blood vessels, into all the tissues of the body.
lymphedema (LIM-fuh-DEE-muh)
A condition in which excess fluid collects in tissue and causes swelling. It may occur in the arm or leg after lymph vessels or lymph nodes in the underarm or groin are removed or treated with radiation.
lymphocyte (LIM-foh-site)
A type of immune cell that is made in the bone marrow and is found in the blood and in lymph tissue. The two main types of lymphocytes are B lymphocytes and T lymphocytes. B lymphocytes make antibodies, and T lymphocytes help kill tumor cells and help control immune responses. A lymphocyte is a type of white blood cell.
lymphoma (lim-FOH-muh)
Cancer that begins in cells of the immune system. There are two basic categories of lymphomas. One kind is Hodgkin lymphoma, which is marked by the presence of a type of cell called the Reed-Sternberg cell. The other category is non-Hodgkin lymphomas, which includes a large, diverse group of cancers of immune system cells. Non-Hodgkin lymphomas can be further divided into cancers that have an indolent (slow-growing) course and those that have an aggressive (fast-growing) course. These subtypes behave and respond to treatment differently. Both Hodgkin and non-Hodgkin lymphomas can occur in children and adults, and prognosis and treatment depend on the stage and the type of cancer.
melanoma (MEH-luh-NOH-muh)
A form of cancer that begins in melanocytes (cells that make the pigment melanin). It may begin in a mole (skin melanoma), but can also begin in other pigmented tissues, such as in the eye or in the intestines.
MRI
A procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed pictures of areas inside the body. These pictures can show the difference between normal and diseased tissue. MRI makes better images of organs and soft tissue than other scanning techniques, such as computed tomography (CT) or x-ray. MRI is especially useful for imaging the brain, the spine, the soft tissue of joints, and the inside of bones. Also called magnetic resonance imaging, NMRI, and nuclear magnetic resonance imaging.
nutrient (NOO-tree-ent)
A chemical compound (such as protein, fat, carbohydrate, vitamin, or mineral) contained in foods. These compounds are used by the body to function and grow.
obese
Having an abnormally high, unhealthy amount of body fat.
ovarian cancer (oh-VAYR-ee-un KAN-ser)
Cancer that forms in tissues of the ovary (one of a pair of female reproductive glands in which the ova, or eggs, are formed). Most ovarian cancers are either ovarian epithelial carcinomas (cancer that begins in the cells on the surface of the ovary) or malignant germ cell tumors (cancer that begins in egg cells).
overweight
Being too heavy for one’s height. Excess body weight can come from fat, muscle, bone, and/or water retention. Being overweight does not always mean being obese.
oxygen (OK-sih-jen)
A colorless, odorless gas. It is needed for animal and plant life. Oxygen that is breathed in enters the blood from the lungs and travels to the tissues.
pelvis
The lower part of the abdomen, located between the hip bones.
physical examination
An exam of the body to check for general signs of disease.
plasma (PLAZ-muh)
The clear, yellowish, fluid part of the blood that carries the blood cells. The proteins that form blood clots are in plasma.
prostate cancer (PROS-tayt KAN-ser)
Cancer that forms in tissues of the prostate (a gland in the male reproductive system found below the bladder and in front of the rectum). Prostate cancer usually occurs in older men.
psychological (SY-koh-LAH-jih-kul)
Having to do with how the mind works and how thoughts and feelings affect behavior.
radiation (RAY-dee-AY-shun)
Energy released in the form of particle or electromagnetic waves. Common sources of radiation include radon gas, cosmic rays from outer space, medical x-rays, and energy given off by a radioisotope (unstable form of a chemical element that releases radiation as it breaks down and becomes more stable).
radiation therapy (RAY-dee-AY-shun THAYR-uh-pee)
The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called irradiation and radiotherapy.
radioactive (RAY-dee-oh-AK-tiv)
Giving off radiation.
risk factor
Something that may increase the chance of developing a disease. Some examples of risk factors for cancer include age, a family history of certain cancers, use of tobacco products, certain eating habits, obesity, lack of exercise, exposure to radiation or other cancer-causing agents, and certain genetic changes.
scanner
In medicine, an instrument that takes pictures of the inside of the body.
sentinel lymph node
The first lymph node to which cancer is likely to spread from the primary tumor. When cancer spreads, the cancer cells may appear first in the sentinel node before spreading to other lymph nodes.
soft tissue
Refers to muscle, fat, fibrous tissue, blood vessels, or other supporting tissue of the body.
spleen
An organ that is part of the lymphatic system. The spleen makes lymphocytes, filters the blood, stores blood cells, and destroys old blood cells. It is located on the left side of the abdomen near the stomach.
surgery (SER-juh-ree)
A procedure to remove or repair a part of the body or to find out whether disease is present. An operation.
symptom
An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.
thymus
An organ that is part of the lymphatic system, in which T lymphocytes grow and multiply. The thymus is in the chest behind the breastbone.
tonsil
One of two small masses of lymphoid tissue on either side of the throat.
tumor (TOO-mer)
An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancer), or malignant (cancer). Also called neoplasm.
uterine cancer (YOO-teh-rin KAN-ser)
Cancer that forms in tissues of the uterus (small, hollow, pear-shaped organ in a woman's pelvis in which a baby grows). Two types of uterine cancer are endometrial cancer (cancer that begins in cells lining the uterus) and uterine sarcoma (a rare cancer that begins in muscle or other tissues in the uterus).
vulvar cancer
Cancer of the vulva (the external female genital organs, including the clitoris, vaginal lips, and the opening to the vagina).
wart
A raised growth on the surface of the skin or other organ.