Last Modified: 08/19/2011
General Information About Lymphedema
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.
1
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 in adults 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.
A grading system is also used to diagnose and describe lymphedema. Grades 1, 2, 3, and 4 are based on size of the affected limb and how severe the signs and symptoms are.
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. Stage III lymphedema rarely occurs in breast cancer patients. Stage III is also called lymphostatic elephantiasis.
Managing Lymphedema
Patients can take steps to prevent lymphedema or keep it from getting worse.
Taking preventive steps may keep lymphedema from developing. Health care providers can teach patients how to prevent and take care of lymphedema at home. If lymphedema has developed, these steps may keep it from getting worse.
Preventive steps include the following:
Tell your health care provider right away if you notice symptoms of lymphedema.
See the General Information 2 section for symptoms that may be caused by lymphedema. Tell your doctor right away if you have any of these symptoms. The chance of improving the condition is better if treatment begins early. Untreated lymphedema can lead to problems that cannot be reversed.
Keep skin and nails clean and cared for, to prevent infection.
Bacteria can enter the body through a cut, scratch, insect bite, or other skin injury. Fluid that is trapped in body tissues by lymphedema makes it easy for bacteria to grow and cause infection. Look for signs of infection, such as redness, pain, swelling, heat, fever, or red streaks below the surface of the skin. Call your doctor right away if any of these signs appear. Careful skin and nail care helps prevent infection:
- Use cream or lotion to keep the skin moist.
- Treat small cuts or breaks in the skin with an antibacterial ointment.
- Avoid needle sticks of any type into the limb (arm or leg) with lymphedema. This includes shots or blood tests.
- Use a thimble for sewing.
- Avoid testing bath or cooking water using the limb with lymphedema. There may be less feeling (touch, temperature, pain) in the affected arm or leg, and skin might burn in water that is too hot.
- Wear gloves when gardening and cooking.
- Wear sunscreen and shoes when outdoors.
- Cut toenails straight across. See a podiatrist (foot doctor) as needed to prevent ingrown nails and infections.
- Keep feet clean and dry and wear cotton socks.
Avoid blocking the flow of fluids through the body.
It is important to keep body fluids moving, especially through an affected limb or in areas where lymphedema may develop.
- Do not cross legs while sitting.
- Change sitting position at least every 30 minutes.
- Wear only loose jewelry and clothes without tight bands or elastic.
- Do not carry handbags on the arm with lymphedema.
- Do not use a blood pressure cuff on the arm with lymphedema.
- Do not use elastic bandages or stockings with tight bands.
Keep blood from pooling in the affected limb.
- Keep the limb with lymphedema raised higher than the heart when possible.
- Do not swing the limb quickly in circles or let the limb hang down. This makes blood and fluid collect in the lower part of the arm or leg.
- Do not apply heat to the limb.
Studies have shown that carefully controlled exercise is safe for patients with lymphedema.
Exercise does not increase the chance that lymphedema will develop in patients who are at risk for lymphedema. In the past, these patients were advised to avoid exercising the affected limb. Studies have now shown that slow, carefully controlled exercise is safe and may even help keep lymphedema from developing. Studies have also shown that, in breast-cancer survivors, upper-body exercise does not increase the risk that lymphedema will develop. (See the Exercise 3 section under Treatment of Lymphedema for more information.)
Treatment of Lymphedema
The goal of treatment is to control the swelling and other problems caused by lymphedema.
Damage to the lymph system cannot be repaired. Treatment is given to control the swelling caused by lymphedema and keep other problems from developing or getting worse. Physical (non-drug) therapies are the standard treatment. Treatment may be a combination of several of the physical methods. The goal of these treatments is to help patients continue with activities of daily living, to decrease pain, and to improve the ability to move and use the limb (arm or leg) with lymphedema. Drugs are not usually used for long-term treatment of lymphedema.
Treatment of lymphedema may include the following:
Pressure garments are made of fabric that puts a controlled amount of pressure on different parts of the arm or leg to help move fluid and keep it from building up. Some patients may need to have these garments custom-made for a correct fit. Wearing a pressure garment during exercise may help prevent more swelling in an affected limb. It is important to use pressure garments during air travel, because lymphedema can become worse at high altitudes. Pressure garments are also called compression sleeves and lymphedema sleeves or stockings.
Both light exercise and aerobic exercise (physical activity that causes the heart and lungs to work harder) help the lymph vessels move lymph out of the affected limb and decrease swelling.
- Talk with a certified lymphedema therapist before beginning exercise.
Patients who have lymphedema or who are at risk for lymphedema should talk with a certified lymphedema therapist before beginning an exercise routine. (See the Lymphology Association of North America 4 Web site for a list of certified lymphedema therapists in the United States.)
- Wear a pressure garment if lymphedema has developed.
Patients who have lymphedema should wear a well-fitting pressure garment during all exercise that uses the affected limb or body part.
When it is not known for sure if a woman has lymphedema, upper-body exercise without a garment may be more helpful than no exercise at all. Patients who do not have lymphedema do not need to wear a pressure garment during exercise.
- Breast cancer survivors should begin with light upper-body exercise and increase it slowly.
Some studies with breast cancer survivors show that upper-body exercise is safe in women who have lymphedema or who are at risk for lymphedema. Weight-lifting that is slowly increased may keep lymphedema from getting worse. Exercise should start at a very low level, increase slowly over time, and be overseen by the lymphedema therapist. If exercise is stopped for a week or longer, it should be started again at a low level and increased slowly.
If symptoms (such as swelling or heaviness in the limb) change or increase for a week or longer, talk with the lymphedema therapist. It is likely that exercising at a low level and slowly increasing it again over time is better for the affected limb than stopping the exercise completely.
More studies are needed to find out if weight-lifting is safe for cancer survivors with lymphedema in the legs.
Once the lymph fluid is moved out of a swollen limb, bandaging (wrapping) can help prevent the area from refilling with fluid. Bandages also increase the ability of the lymph vessels to move lymph along. Lymphedema that has not improved with other treatments is sometimes helped with bandaging.
The goal of skin care is to prevent infection and to keep skin from drying and cracking. See skin care tips, in the Managing Lymphedema 5 section.
Combined physical therapy is a program of massage, bandaging, exercises, and skin care managed by a trained therapist. At the beginning of the program, the therapist gives many treatments over a short time to decrease most of the swelling in the limb with lymphedema. Then the patient continues the program at home to keep the swelling down. Combined therapy is also called complex decongestive therapy.
Compression devices are pumps connected to a sleeve that wraps around the arm or leg and applies pressure on and off. The sleeve is inflated and deflated on a timed cycle. This pumping action may help move fluid through lymph vessels and veins and keep fluid from building up in the arm or leg. Compression devices may be helpful when added to combined therapy. The use of these devices should be supervised by a trained professional because too much pressure can damage lymph vessels near the surface of the skin.
In patients who are overweight, lymphedema related to breast cancer may improve with weight loss.
Laser therapy may help decrease lymphedema swelling and skin hardness after a mastectomy. A hand-held, battery-powered device is used to aim low-level laser beams at the area with lymphedema.
Lymphedema is not usually treated with drugs. Antibiotics may be used to treat and prevent infections. Other types of drugs, such as diuretics or anticoagulants (blood thinners), are usually not helpful and may make the lymphedema worse.
Lymphedema caused by cancer is rarely treated with surgery.
Massage therapy (manual therapy) for lymphedema should begin with someone specially trained in treating lymphedema. In this type of massage, the soft tissues of the body are lightly rubbed, tapped, and stroked. It is a very light touch, almost like a brushing. Massage may help move lymph out of the swollen area into an area with working lymph vessels. Patients can be taught to do this type of massage therapy themselves.
When done correctly, massage therapy does not cause medical problems. Massage should not be done on any of the following:
- Open wounds, bruises, or areas of broken skin.
- Tumors that can be seen on the skin surface.
- Areas with deep vein thrombosis (blood clot in a vein).
- Sensitive soft tissue where the skin was treated with radiation therapy.
When lymphedema is severe and does not get better with treatment, other problems may be the cause.
Sometimes severe lymphedema does not get better with treatment or it develops several years after surgery. If there is no known reason, doctors will try to find out if the problem is something other than the original cancer or cancer treatment, such as another tumor.
Lymphangiosarcoma is a rare, fast-growing cancer of the lymph vessels. It is a problem that occurs in some breast cancer patients and appears an average of 10 years after a mastectomy. Lymphangiosarcoma begins as purple lesions on the skin, which may be flat or raised. A CT scan or MRI is used to check for lymphangiosarcoma. Lymphangiosarcoma usually cannot be cured.
Current Clinical Trials
Check NCI’s list of cancer clinical trials for U.S. supportive and palliative care trials about lymphedema 6 that are now accepting participants. The list of trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site 7.
Changes to This Summary (08/19/2011)
The PDQ cancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.
Changes were made to this summary to match those made to the health professional version.
Questions or Comments About This Summary
If you have questions or comments about this summary, please send them to Cancer.gov through the Web site’s Contact Form 8. We can respond only to email messages written in English.
Get More Information From NCI
Call 1-800-4-CANCER
For more information, U.S. residents may call the National Cancer Institute's (NCI's) Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237) Monday through Friday from 8:00 a.m. to 8:00 p.m., Eastern Time. A trained Cancer Information Specialist is available to answer your questions.
Chat online
The NCI's LiveHelp® 9 online chat service provides Internet users with the ability to chat online with an Information Specialist. The service is available from 8:00 a.m. to 11:00 p.m. Eastern time, Monday through Friday. Information Specialists can help Internet users find information on NCI Web sites and answer questions about cancer.
Write to us
For more information from the NCI, please write to this address:
- NCI Public Inquiries Office
- Suite 3036A
- 6116 Executive Boulevard, MSC8322
- Bethesda, MD 20892-8322
Search the NCI Web site
The NCI Web site 10 provides online access to information on cancer, clinical trials, and other Web sites and organizations that offer support and resources for cancer patients and their families. For a quick search, use the search box in the upper right corner of each Web page. The results for a wide range of search terms will include a list of "Best Bets," editorially chosen Web pages that are most closely related to the search term entered.
There are also many other places to get materials and information about cancer treatment and services. Hospitals in your area may have information about local and regional agencies that have information on finances, getting to and from treatment, receiving care at home, and dealing with problems related to cancer treatment.
Find Publications
The NCI has booklets and other materials for patients, health professionals, and the public. These publications discuss types of cancer, methods of cancer treatment, coping with cancer, and clinical trials. Some publications provide information on tests for cancer, cancer causes and prevention, cancer statistics, and NCI research activities. NCI materials on these and other topics may be ordered online or printed directly from the NCI Publications Locator 11. These materials can also be ordered by telephone from the Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237).
About PDQ
PDQ is a comprehensive cancer database available on NCI's Web site.
PDQ is the National Cancer Institute's (NCI's) comprehensive cancer information database. Most of the information contained in PDQ is available online at NCI's Web site 10. PDQ is provided as a service of the NCI. The NCI is part of the National Institutes of Health, the federal government's focal point for biomedical research.
PDQ contains cancer information summaries.
The PDQ database contains summaries of the latest published information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries are available in two versions. The health professional versions provide detailed information written in technical language. The patient versions are written in easy-to-understand, nontechnical language. Both versions provide current and accurate cancer information.
The PDQ cancer information summaries are developed by cancer experts and reviewed regularly.
Editorial Boards made up of experts in oncology and related specialties are responsible for writing and maintaining the cancer information summaries. The summaries are reviewed regularly and changes are made as new information becomes available. The date on each summary ("Date Last Modified") indicates the time of the most recent change.
PDQ also contains information on clinical trials.
A clinical trial is a study to answer a scientific question, such as whether one method of treating symptoms is better than another. Trials are based on past studies and what has been learned in the laboratory. Each trial answers certain scientific questions in order to find new and better ways to help cancer patients. Some patients have symptoms caused by cancer treatment or by the cancer itself. During supportive care clinical trials, information is collected about how well new ways to treat symptoms of cancer work. The trials also study side effects of treatment and problems that come up during or after treatment. If a clinical trial shows that a new treatment is better than one currently being used, the new treatment may become "standard." Patients who have symptoms related to cancer treatment may want to think about taking part in a clinical trial.
Listings of clinical trials are included in PDQ and are available online at NCI's Web site 7. Descriptions of the trials are available in health professional and patient versions. Many cancer doctors who take part in clinical trials are also listed in PDQ. For more information, call the Cancer Information Service 1-800-4-CANCER (1-800-422-6237).
Glossary Termsabdomen (AB-doh-men)The area of the body that contains the pancreas, stomach, intestines, liver, gallbladder, and other organs.abnormal (ab-NOR-mul) 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 (blud) 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 (blud VEH-sel) 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 a cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is a cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is a 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. Also called malignancy.capillary (KA-pih-layr-ee) 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 (KLA-vih-kul) One of a pair of bones at the base of the front of the neck. The clavicles connect the breastbone to the shoulder blades. Also called collarbone.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 (fy-BROH-sis) 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 (groyn) The area where the thigh meets the abdomen.infection (in-FEK-shun) 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 (in-JEK-shun) 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 (limf node DRAY-nij) 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 extra lymph fluid builds up in tissues and causes swelling. It may occur in an arm or leg if lymph vessels are blocked, damaged, or removed by surgery.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.lymphoscintigraphy (LIM-foh-sin-TIH-gruh-fee) A method used to check the lymph system for disease. A radioactive substance that flows through the lymph ducts and can be taken up by lymph nodes is injected into the body. A scanner or probe is used to follow the movement of this substance on a computer screen. Lymphoscintigraphy is used to find the sentinel lymph node (the first node to receive lymph from a tumor), which may be removed and checked for tumor cells. Lymphoscintigraphy is also used to diagnose certain diseases or conditions, such as lymphoma or lymphedema.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 (oh-BEES) 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 (OH-ver-WAYT) 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.PDQ PDQ is an online database developed and maintained by the National Cancer Institute. Designed to make the most current, credible, and accurate cancer information available to health professionals and the public, PDQ contains peer-reviewed summaries on cancer treatment, screening, prevention, genetics, complementary and alternative medicine, and supportive care; a registry of cancer clinical trials from around the world; and directories of physicians, professionals who provide genetics services, and organizations that provide cancer care. Most of this information, and more specific information about PDQ, can be found on the NCI's Web site at http://www.cancer.gov/cancertopics/pdq. Also called Physician Data Query.pelvis (PEL-vus) The lower part of the abdomen, located between the hip bones.physical examination (FIH-zih-kul eg-ZA-mih-NAY-shun) 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 (... FAK-ter) Something that increases the chance of developing a disease. Some examples of risk factors for cancer are age, a family history of certain cancers, use of tobacco products, being exposed to radiation or certain chemicals, infection with certain viruses or bacteria, and certain genetic changes.scanner (SKA-ner) In medicine, an instrument that takes pictures of the inside of the body.sentinel lymph node (SEN-tih-nul limf 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 (... TIH-shoo) Refers to muscle, fat, fibrous tissue, blood vessels, or other supporting tissue of the body.spleen (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 (SIMP-tum) An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.thymus (THY-mus) 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 (TON-sil) 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 (the small, hollow, pear-shaped organ in a woman's pelvis in which a fetus develops). 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 (VUL-ver KAN-ser) Cancer of the vulva (the external female genital organs, including the clitoris, vaginal lips, and the opening to the vagina).wart (wort) A raised growth on the surface of the skin or other organ. |