What is Lymphedema?

Types of Lymphedema

Lymphedema, also spelled lymphoedema, is a condition that occurs when the lymphatic drainage system is impaired to the extent that the amount of lymphatic fluid within a given area exceeds the capacity of the lymphatic transport system to remove it. Lymphedema is a chronic condition and once an individual is at risk of developing it, this risk remains throughout life. The onset of the swelling can be sudden, or gradual.

The swelling of lymphedema is caused by the inability of lymph to drain normally and this produces tissues that are swollen with protein-rich stagnant lymph. When there is even the slightest break in the skin, bacteria can enter and thrive in this fluid. Here they reproduce quickly and cause serious infections that spread rapidly.

The two principle types of lymphedema are primarly and secondary lymphedema. [1]

Primary Lymphedema (PLE)

PLE present in this child since birth. ©Lymph Notes

Primary lymphedema is a genetic disorder in which lymphatic vessels fail to develop properly. The University of Pittsburgh Lymphedema Family Study has identified several genes that cause this condition and research indicates that potentially more genes are involved. According to estimates from the US Department of Health and Human Services, PLE occurs in between 1/6,000 and 1/3000 live births. This implies 50,000 to 1,000,000 carriers of this gene in the US. [2]

PLE is caused by lymphatic vessels that have failed to develop properly before birth. This condition is commonly subdivided based on the age of onst when symptoms begin to develop:

• Congenital lymphedema, which is also known as Milroy’s syndrome, has visible swelling that can be detected on a prenatal ultrasound, is present at birth or develop within the first two years of life. [3] This form represents 10-25 percent of all PLE cases with females affected twice as often as males.
• When swelling is present at birth, further diagnostic investigation should be conducted soon after birth because it could be a symptom of other conditions such as Turner syndrome.
• Lymphedema praecox, also known as Meige Disease, is PLE that appears between puberty and the age of 35 years. Approximately 75 percent of all PLE cases develop within this age span with the majority occurring during adolescence. This condition occurs in four times as many females as males and usually only one leg is affected. [4] With treatment to control the swelling, most mature females with primary lymphedema are able to live normal lives including bearing children. For details, see Pregnancy and Primary Lymphedema.
• Lymphedema tarda, which is the rarest form of PLE, accounts for only 10% of all cases. This does not become clinically evident until after the age of 35 years or older with swelling in one or both legs. The onset is often of sudden onset and of unknown cause. In some cases there may be a minor incident, such as an insect bite, followed by the swelling of the affected limb. Although the insect bite heals, the swelling does not go away. [5]

SLE of the left arm after breast cancer treatment. © Lymph Notes

Secondary Lymphedema (SLE)

Secondary lymphedema is an acquired disorder caused by damage to the lymphatic system. Cancer treatment is the largest single cause of SLE; however it can also be due to injuries, surgery, burns, scars, and obesity.

Additional Forms of Lymphedema

SLE usually develops adjacent to lymphatic structures that have been removed or damaged. Although the most commonly diagnosed cases occur in the arms and legs, lymphedema also affects other body parts and are named for the affected area or for the cause.

• Head and Neck lymphedema is a build-up of lymph above the shoulders and collar bone. To learn more read Head and Neck Lymphedema.
• Truncal lymhedema affects the upper portion of the body. To learn more read Truncal Lymphedema.
• Lymphatic malformations are serious, and rare, conditions that require specialized treatment. For details, read Lymphatic Malformations.
• Malignant lymphedema is swelling caused by a rapidly growing tumor that places pressure on the lymph nodes and obstructs the flow of lymph. It is the tumor, not the lymphedema, which is malignant. For details, read Malignant Lymphedema.
• Filariasis, which is common in some developing countries, is caused by a parasitic worm. It is unlike either PLE or SLE and is treated using entirely different methods. For details, read Filariasis.

The Stages of Lymphedema

Lymphedema is a progressive disease and a staging system is used as a shorthand method of describing the severity of a patient’s lymphedema.[6]

Although commonly described as a three-part staging system, four stages are now recognized. The added stage, known as Stage 0, recognizes the preclinical stage of lymphedema before symptoms are apparent.

• In Stage 0 lymphedema, which is also known as the subclinical state, swelling is not evident. This stage may exist for many months or years before the edema becomes evident. If the condition is detected early in this stage, there is the possibility of preventing the condition from developing.
• In Stage 1 lymphedema, the swelling tissues are soft to the touch and pitting edema is present. During this stage the swelling can temporarily be reduced by elevation of the limb; however, the swelling soon returns. Stage 1 lymphedema can be managed with early treatment and often improves greatly.
• In Stage 2 lymphedema the accumulated fluid does not reduce on elevation. The tissues feel firm, even hard, and testing for pitting edema leaves makes only a slight indentation. Stage 2 lymphedema can be improved with appropriate treatment.
• In Stage 3 lymphedema the swelling and tissue fibrosis cause the skin to thicken and lose its normal elasticity. These changes create tissue folds that limit mobility, are disfiguring, and encourage fungal infections and open wounds that are difficult to heal. Stage 3 lymphedema can be improved with intense therapy and it can be prevented from becoming worse; however, it is rarely reversed to an earlier stage. [7]

How Common is Lymphedema?

Accurate statistics on the prevalence of lymphedema are difficult to determine. One reason is that many cases are never diagnosed accurately. Another reason is that it is often not reported. The following figures provide estimates from several sources.

The US Department of health and Human Services estimates that lymphedema affects an estimated 100 million men, women, and children around the world including at least 3 million Americans. [2] Other researchers place this number at over 200 million people. [3]

In June 2004, The Centers for Disease Control and Prevention (CDC) announced that there are presently about 10 million cancer survivors in the US. This figure continues to grow.

Most sources estimate that between 20 to 40% of these survivors will develop lymphedema at some point in their lifetime with higher percentages among the elderly.

In 2006, Robert Weiss did a literature study on this topic and his results can be found in the article titled The Incidence of Lymphedema.

Using a 30% rate of developing lymphedema these figures indicate that there are approximately 3 million cases of lymphedema in the US caused by cancer treatment alone. This figure does not take into consideration primary lymphedema or secondary lymphedema due to other causes.

References

[1] Lymphedema Diagnosis and Therapy 2-E, edited by H. Weissleder and C. Schuehhardt. Kagerer Kommunikation, 1997.

[2] “Advances in Our Understanding of the Genetics of lymphoedema: From Diagnosis to Treatment” by N.B Piller. Lymph Link. Vol 20 #2  2008, pages 1-31

[3] “Management of Childhood and Adolescent Lymphedema” by J.L. Feldman, Lymph Link, Vol 16:2 April-June 2004, p. 1.

[4] “Lymphedema praecox” by D. R. Revis Jr, MD, Department of Surgery, Division of Plastic and Reconstructive Surgery, University of Florida College of Medicine. Updated March 18, 2008.

[6] “The Diagnosis and Treatment of Peripheral Lymphedema: Consensus Document of the International Society of Lymphology.” Lymphology 42, 2009, p. 51-60.

[7] “Estimating the population burden of lymphedema” by S.G. Rockson, K.K. Rivera. Ann NY Acad Sci. 2008;1131:147-54

© LymphNotes 2009. This information does not replace the advice of a qualified health care professional.

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Category: What is Lymphedema? Updated: 2011-11-17