What is Lymphoedema?
Lymphoedema is a collection of lymph fluid in the body tissues.
In every person there is a small amount of fluid (lymph) in the body tissues. This lymphatic fluid is fluid that has left the blood system. Normally most of this fluid is collected by a system of drainage tubes, similar to blood vessels, called the lymphatic system. There is a particularly well developed system of lymphatics in the intestines (lacteals) that absorb nutrients after ingested food has been broken down.
The movement of fluid through the lymphatic system is aided by contraction of muscles and there is also a gentle pumping action from the lymphatic vessels themselves. The fluid is filtered through lymph nodes and then eventually drains back to the venous circulation through a major vein on the left side of the neck. Lymph only flows in one direction and there are tiny valves in the lymphatic channels which aid in this one way flow.
Lymph usually moves at about 120 mls/hr and about 2-4 litres of lymph are moved around the body each day. There is great redundancy in the lymphatic system which usually operates at about one tenth of its maximum load. When lymph load is too great, fluid accumulates in tissues rather than draining back into the blood stream and lymphoedema develops.
Why does Lymphoedema occur?
Lymphoedema can occur for no apparent reason (Primary lymphoedema) or it can occur as a consequence of another problem (Secondary lymphoedema).
Normal lymphatic vessels can increase the flow of lymph ten times if required. Because of this large reservoir capacity of the lymph system an increase in the formation of lymph fluid on its own does not cause lymphoedema. There must be some abnormality or problem with the lymphatic system itself.
In primary lymphoedema the lymphatic vessels themselves often appear to be abnormal. They can be very poorly developed (hypoplastic) or not developed at all (aplastic). Tiny valves in the lymphatics may also be faulty. Why this occurs is not entirely clear, but genetic abnormalities have been identified in some patients.
Primary lymphoedema can be divided into two main groups
1. Congenital onset primary lymphoedema
This can be a familial problem such as Milroy's disease which involves swelling below the knee. It may also be sporadic as in lymphatic malformations, Turner's syndrome and in other rare syndromes.
2. Post pubertal primary lymphoedema
This can also be a familial condition as in Distichiasis-lymphoedema associated with abnormalities of the eyelashes. It may also be sporadic as in inguinal node sclerosis or yellow-nail syndrome.
Lymphoedema praecox and lymphoedema tarda only refer to the age at which lymphoedema develops. Lymphoedema praecox develops in adolescence and Lymphoedema tarda generally after the age of 35 years. It is not known why normal adults, without known precipitating factors, should develop lymphoedema, but women are affected more commonly.
In secondary lymphoedema the accumulation of fluid is because of another problem.
1. Cancer and radiotherapy
After certain types of surgery (breast surgery, node dissection for melanoma) the lymphatics are intentionally removed to reduce the risk of cancer recurrence. As a part of the treatment for some breast cancer or melanoma an axillary clearance may be performed in which all or most of the lymphatic tissue in the armpit is removed (axillary clearance). In melanoma and sometimes in other types of cancer a similar procedure is performed at the top of the leg in the groin (groin clearance). Although in many patients other lymphatics can compensate for the loss of lymphatic tissue, in some patients this is not enough and lymphoedema develops in the arm or the leg. Significant lymphoedema occurs in about 10% (1 in 10) of breast cancer patients. This can also occur after radiotherapy which can damage lymphatic vessels. In patients who have had both surgery and radiotherapy there is an even greater risk of developing lymphoedema. After surgery lymphoedema may not develop immediately. It can develop gradually as the operation site heals by the formation of scar tissue. About one third of the patients who develop lymphoedema will do so more than one year after their breast cancer surgery.
In some patients the development of cancers themselves can lead to lymphoedema. This is because sometimes the tumour cells invade the lymphatic vessels, blocking them.
In tropical countries a tiny worm infection (filariasis) in the lymphatics can lead to massive lymphoedema (elephantiasis) of the legs and genital area. The skin also becomes very thickened and with overhanging folds which can resemble the foot of an elephant. This is because the worm is present in the lymphatic vessels and it blocks the flow of lymph fluid. Filariasis is the most common form of secondary lymphoedema worldwide.
Cellulitis is a common soft tissue infection in which the tissues become red, hot, swollen and tender. This typically occurs in the lower leg but can develop anywhere in the body. In severe infections the inflammation can spread to the lymphatics (lymphangitis) and cause damage by leading to scarring around the lymphatics as the inflammatory process resolves. Frequent damage to the lymphatics caused by infection can also lead to swelling because of scarring around the lymphatic channels.
What problems can Lymphoedema cause?
Swelling - Initially lymphoedema may only cause cosmetic concerns or heaviness and difficulty with some movements. This is because the leg (or arm) that is affected will be swollen and the skin may become slightly shiny. It also contains extra fluid so will feel heavier, because it is heavier. This may be all that happens in some patients.
Cellulitis - the presence of extra tissue fluid causing swelling in the leg can also make the patient more likely to develop infection in the tissues (cellulitis). The lymph fluid itself is very rich in protein and is an ideal fluid for bacterial growth. This can occur even after a minor injury. When this occurs the leg can swell to a greater extent. It will become red, tender and painful and the patient will probably feel generally unwell. This problem can usually be treated effectively with antibiotics, bedrest and elevation of the limb.
Fibrosis - the mere presence of significant amounts of lymph fluid in the tissues over many years can lead to scarring and fibrosis of the tissues. Once infection and inflammation resolve there will inevitably be some residual scar damage to the tissues of the leg leading to slightly more swelling than before. This puts the leg at a slightly greater risk of infection. A vicious cycle can then develop with further infection leading to further swelling and so on. It is important to try and halt this process at an early stage when most of the changes in the leg are at a reversible stage. As well as swelling due to lymphoedema, the skin can become very thickened (hyperkeratosis) and abnormal. Ulceration may occur in severe cases.
Tumours - very rarely tumours (lymphangiosarcoma) can develop in the chronically inflamed tissues. This is sometimes called Stewart-Treves syndrome.
How is Lymphoedema diagnosed?
The diagnosis of lymphoedema is made by your doctor taking a careful medical history and examining the affected areas. This is often sufficient to decide lymphoedema is the likely cause. Lymphoscintigraphy or lymphangiography can sometimes be used to confirm the cause and give further information.
Lymphangiography is a predominantly anatomical test outlining the channels along which lymph drains. It was never widely used because of the difficulties cannulating tiny lymphatic channels and a potential risk of damage to the lymphatic system itself. Radionuclide lymphoscintigraphy was introduced in the 1950s and tells us much more about the function of the lymphatics and how well they are working. This is an easier test to perform and has become the gold standard. In most patients it is not necessary to perform either test.
Gadolinium enhanced magnetic resonance scans (MRI) may also be helpful for diagnosis and to exclude other potential pathologies.
Sometimes other tests may be necessary to exclude other conditions. Imaging of the veins may be required to ensure they are working normally.
What treatment is available?
Treatment for lymphoedema needs to be intensive and lifelong. Lymphoedema cannot usually be cured, but it can be controlled. Benefits can be obtained from the treatments detailed below, but if they are stopped then problems tend to re-occur. There is debate about whether lymphoedema can be prevented. Breast cancer patients who have undergone surgery to the armpit are usually advised to avoid any procedures, such as having blood taken, from the arm on the same side. They are also advised to avoid insertion of drips and vaccination on the same side as axillary surgery.
Massage and manual lymphatic drainage (MLD) - Intensive massage by practitioners trained in specific techniques is helpful in managing lymphoedema.
This massage is based on creating spaces in the tissues and then massaging fluid into these spaces and away from the limb. To do this the massage needs to start at the part of the limb where it attaches to the trunk where the lymphatics are relatively normal. The lymphoedema therapist then massages fluid away from this area towards the trunk. The massage then works gradually towards the hand or foot. This therapy may need to continue for some weeks until the decrease in swelling is satisfactory. It is time consuming but is one of the most effective treatments.
Compression stockings and bandaging- Compression stockings are crucial in maintaining the benefits produced from massage. Graduated high compression stockings help prevent swelling from re-accumulating once it has been reduced by massage. It is important that stockings are worn at all times, except when the legs are elevated in bed at night. Bandaging is frequently used when swelling is severe. A combination of bandaging and massage can reduce limb size and then compression stockings can be fitted.
Patients with lymphoedema usually need to wear the high grade compression stockings. These can be troublesome to put on, but are very beneficial in reducing swelling. Custom made stockings may be required initially to get control of the oedema and allow more standard stockings to be worn.. Stockings require replacement approximately every 4-6 months, as they begin to lose their compressive effect.
Drugs – Medical treatment for lymphoedema is rarely helpful..
Diuretics or water tablets that promote the passage of more urine are generally ineffective for lymphoedema. Patients will pass more urine but what fluid remains will still gravitate to the affected limb. This is because there is a local problem present leading to lymph retention and it is not due to excess fluid thoughout the whole body.
Surgery - Surgery has a very limited role in patients with lymphoedema. It is hardly ever required and will not be curative. Despite this two main types of operations have been developed. Firstly, in very particular types of patients some form of bypass or drainage procedure may be attempted to drain off the excess lymph fluid from the affected limb. Secondly, in patients with very severely affected limbs debulking operations have been performed to reduce the size of the affected limb by removing excess tissue.
Skin Care and control of infection - it is important to keep the skin in good condition. Regular hygiene particularly in skin creases and between the toes is essential. Anti-fungal powders can be helpful. Simple moisturising creams can be helpful for flaky skin. It is important to take minor wounds seriously and not to allow them to develop into serious problems. Minor infections should be treated aggressively with antibiotics.
Weight loss - many lymphoedema patients are overweight. This situation compounds any existing problems and weight loss is essential to achieve benefits from any other treatments.