Overview I Diagnosis I Treatment I Frequently Asked Questions
Lymphatic malformations are slow-flow vascular malformations due to a localized abnormality affecting the development of the lymphatic system. The lymphatic system is a network of small channels that carry a clear fluid called lymph from the body tissues and organs back to the bloodstream. When a lymphatic malformation occurs, multiple cysts (which are sacs containing clear fluid called lymph) result. These cysts vary in size; the small cysts are called microcysts and the large cysts are called macrocysts. Cysts of variable size can occur in one lymphatic malformation. As these are vascular malformations, they are present at birth and grow proportionately to the child.
The microcystic lymphatic malformations can infiltrate tissues within the body such as skin, mucous membranes, bone and other organs. The macrocystic lymphatic malformations often create large swellings under normal skin. Lymphatic malformations can vary in their size and the extent of involvement within the body tissues. They can cause expansion of affected areas, for example, enlargement of an arm, hand or side of the neck. Lymphatic malformations vary in size and colour from time to time because of inflammation, infection and bleeding within the malformation.
When lymphatic malformations involve the skin, sometimes clear fluid and small amounts of blood leak from the malformation. When bleeds occur into some lymphatic malformations, the skin overlying the lymphatic malformation can look bruised. Bleeding and infection can cause sudden expansion of the lymphatic malformation which is worrying if it is located near a vital structure such as the airway (the breathing passage from the mouth to the lungs). Large, extensive lymphatic malformations may be associated with blood clotting abnormalities and serious bloodstream infections. When a lymphatic malformation occurs within an arm or leg, it is likely that the affected arm or leg will have good function.
(A) Enlargement of the leg due to an extensive microcystic lymphatic malformation. (B) Lymphatic malformation of the arm, also affecting the skin.
(A) Enlarged finger due to microcystic lymphatic malformation. (B) Discolouration of same finger due to bleeding within the lymphatic malformation.
Lymphatic malformations may occur in syndromes (an association of several clinically recognizable features), such as Klippel-Trenaunay Syndrome.
A lymphatic malformation is different from a condition known as lymphedema. In lymphedema, there is swelling of tissue with fluid as a result of a blockage or interruption of the lymphatic channels. In babies and young children, the reduced drainage of lymph may be congenital (a condition you are born with) or inherited, and can be associated with certain syndromes (which are associations of several clinically recognizable features) such as Turners and Noonan’s syndromes.
Patients with lymphatic malformations who have involvement of the skin and mucous membranes can often be diagnosed by history and physical examination. Lymphatic malformations that are present in deeper locations are diagnosed on MRI and ultrasound scan. These will confirm the diagnosis and provide excellent information regarding the extent of the abnormality. Occasionally, other investigations such as blood testing are required.
Macrocystic lymphatic malformations can sometimes be detected on antenatal scanning in a baby before birth.
(A) MRI scan showing macrocystic a lymphatic malformation in the chest wall. (B) Ultrasound of a lymphatic malformation: larger and smaller cysts (macro and microcysts) are shown.
There are several treatment options to consider for children with lymphatic malformations. Some children require no specific treatment as they may have no problems related to the lymphatic malformation. For children with extensive lymphatic malformations, such as involving an entire arm or leg, there is no ‘quick fix’ treatment.
It is important to evaluate whether the lymphatic malformation is microcystic or macrocystic or both. This, together with the location of the lymphatic malformation, and knowing any problems the malformation is causing will help determine the correct treatment. Treatment options include surgical excision, radiological injection treatments and laser therapy. Radiological treatments called injection sclerotherapy can be undertaken to shrink the lymphatic malformation. These treatments are carried out by interventional radiologists in Image Guided Therapy.
Injection sclerotherapy often needs to be repeated, usually at frequent intervals. For the larger macrocystic lymphatic malformations, a small tube may be placed through the skin into the cyst to drain fluid from the cyst and help the injection sclerotherapy. This tube is temporary and usually removed after one day. Injection sclerotherapy avoids scarring, which sometimes can be extensive when multiple surgeries are undertaken. Sometimes, surgical excision of the lymphatic malformation may be possible either without or following injection sclerotherapy. The reappearance of a microcystic lymphatic malformation can occur following surgical excision including reappearance at the surgical scar.
Rarely, in patients with extensive lymphatic malformations, abnormalities of blood clotting can be seen on blood testing and some may require treatment for this.
What types of treatments are available for lymphatic malformations?
There are 2 types of lymphatic malformations: small cysts (microcysts) and large cysts (macrocysts). Macrocystic lymphatic malformations can be treated by surgical excision or injection sclerotherapy. Depending on the problems due to the lymphatic malformation, the location in the body, the degree of tissue involvement and the size of the lymphatic malformation, surgery may be offered to some patients. Sometimes injection sclerotherapy can help microcystic lymphatic malformations. Injection sclerotherapy avoids scarring, which sometimes can be extensive when multiple surgeries are undertaken.
Large swelling in the neck due to a macrocystic lymphatic malformation and normal appearance of the same case following sclerotherapy treatment.
Why aren't all lymphatic malformations surgically removed?
Some lymphatic malformations are extensive due to microcysts causing tissue enlargement (for example, such as an entire arm) and may not be suitable for surgical excision. The lymphatic malformation may involve vital structures such as nerves and blood vessels and surgery would be difficult and highly risky. Reappearance of the lymphatic malformation can occur following surgery when this is performed for microcystic lymphatic malformations.
Does wearing a compression garment help with lymphatic malformations?
The compression garment can reduce the swelling due to lymphedema, if this is present in addition to the lymphatic malformation. If there is no lymphedema, then a compression garment does not generally help.
I find the cost of continuously purchasing compression garments very expensive. What should I do?
A compression garment is a medical device and your doctor at SickKids will provide you with a prescription for this. Your insurance company may cover part of the cost of your compression garment and will likely require that a prescription be provided to them. The physiotherapists at the Vascular Anomalies Clinic can provide you with more information about compression garments and other options that may be available for subsidizing their cost.
Is this considered a disability? (Do I qualify for disability benefits or services?)
A lymphatic malformation may or may not be considered a disability. This is evaluated on an individual basis.
Why does a lymphatic malformation cause pain?
If there is sudden expansion due to bleeding or infection, the lymphatic malformation can be painful. The pain will improve when this expansion begins to improve.
How many injection sclerotherapy treatment sessions are needed to treat a lymphatic malformation?
Usually, several injection sclerotherapy treatments are required. This is to ensure that good closure of the malformation is achieved. Treatments need to be at frequent intervals to prevent re-opening of the lymphatic malformation. The number of treatments is determined by the improvement in symptoms. At SickKids, we initially arrange 3 injection sclerotherapy treatments at 6 week intervals and then decide if further treatment is required.
What can I do to deal with my lymphatic malformation at school?
If your lymphatic malformation affects your ability to write or use a keyboard or move between classes in the allotted time, it is encouraged that you speak to someone at your school about this. A school may make arrangements to accommodate you and may require a medical note.
After the age of 18, where are patients with lymphatic malformations treated?
When you reach 18 years of age, if your care needs to be continued, the clinic will arrange transfer of care to an adult clinic in Toronto. If, however, you do not need immediate transfer of care, the clinic will provide you with the necessary contact information for an adult clinic in Toronto.