Lymphatic Malformations

Lymphatic malformations are groups of enlarged and/or misshaped lymphatic channels that do not work correctly. The lymphatic system consists of organs (spleen, thymus, tonsils and adenoids), lymph nodes and thin tubes (called lymphatic vessels) which carry lymphatic fluid. The lymphatic system is an important part of the immune system. It also helps remove extra fluid from the tissues of the body.

In lymphatic malformations, movement of lymphatic fluid into veins is slow or decreased. This causes extra fluid to collect and to enlarge the lymphatic channels. This, results in swelling of the affected area.

Lymphatic malformations form prior to birth. They are thought to be caused by problems in the formation and development of the lymphatic vessels during pregnancy. Lymphatic malformations are not caused by any drug, medication or environmental factor that the baby may have been exposed to during the pregnancy. Most lymphatic malformations are identified at birth or within 2 years of age. Some may not be noticed until the teenage years or early adulthood.

Lymphatic malformations may involve any area of the body. They are most common in the head and neck areas. They can involve one or more body areas. Symptoms and the complications vary and depend on the size and the location of the malformation.

Lymphatic malformations were previously called lymphangiomas or cystic hygromas.

What do lymphatic malformations look like?

Lymphatic malformations have variable appearances. Depending on the size of the abnormal lymphatic channels, they are considered macrocystic, microcystic or a combination of both.

Macrocystic lymphatic malformations are large fluid-filled cysts that look like soft, smooth masses under normal or blue-colored skin.

The microcystic type are sponge-like and look like an area of swelling. Microcytic lymphatic malformations may also have lymphatic blebs over the lesion. Lymphatic blebs are small, raised sacs containing clear lymphatic fluid. These blebs look like blisters. They may also become dark purple or black when blood oozes into the blebs.

Both macrocystic and microcystic malformations may cause enlargement of any body part (e.g., the lip, cheek, ear, tongue, limb, finger, or toe). Some lymphatic malformations are completely internal and cannot be seen.

How are lymphatic malformations diagnosed?

Medical history and physical examination are used to diagnose a lymphatic malformation.

Radiologic imaging such as ultrasonography, magnetic resonance imaging (MRI), or computed tomography (CT or CAT scan) may be needed to confirm diagnosis or to see the extent of the malformation.

What are the possible complications of a lymphatic malformation?

Infection of the skin or soft tissues (cellulitis) may occur due to non-moving lymphatic fluid in the malformation. This may also be due to bacteria entering the body through open lymphatic blebs. Cellulitis could lead to a more serious or life-threatening infection. Immediate treatment with antibiotics is required to treat these skin and soft tissue infections. Bleeding into the area of the malformation may cause pain and growth of the malformation. This may occur from trauma to the area or without reason. The blebs on the skin may bleed or leak lymphatic fluid. Chronic pain and deformity may also occur.

Additional complications may be possible, such as:

A lesion involving the windpipe, tongue or chest can cause difficulty breathing.
A lesion in the stomach and intestines can cause protein loss.
A lesion in the chest can cause chylothorax. This is a leakage of lymphatic fluid into the chest cavity and/or lungs. It can also cause heart and breathing complications.
A lesion in the abdomen can cause chylous ascites. This is a leakage of lymphatic fluid into the abdomen.

Individuals with lymphatic malformations in the head and neck area, especially those involving the mouth, can get frequent and serious infections. This happens because of bacteria from the mouth get into the malformation. Good oral hygiene decreases these infections. Regular tooth brushing and visits to the dentist are recommended.

Diffuse Lymphatic Malformations

Generalized lymphatic anomaly (GLA) and Gorham-Stout disease (GSD) are complicated lymphatic malformations that involve multiple body sites. The areas most affected include: the bones, chest, skin, spleen, liver and gastrointestinal tract. In both GLA and GSD, the lymphatic malformations involve the bones but look different on imaging. Gorham-Stout disease, also called “vanishing bone disease”, is characterized by lymphatic malformations that cause destruction of the outermost layer of the bone (cortex) and bone loss. In GLA, the bones have “punched out” lesions or holes. These bony lesions may result in fractures in both GSD and GLA. These conditions are frequently not identified until after a bone fracture. If the spine is involved, there is a risk of neurological issues.

Patients with GLA and GSD have an increased risk of effusions, which occurs when lymphatic fluid leaks into the lungs or abdomen or around the heart. Individuals with GLA and GSD have other complications depending on locations of the malformation.

Kaposiform lymphangiomatosis (KLA) is rare disorder that is similar to GLA but is more aggressive and can be life-threatening. It is characterized by unusual “kaposiform” lymphatic clusters in multiple body sites. Individuals with KLA often have effusions, bone lesions and involvement of one or more organ. It is associated with coagulopathy (clotting and bleeding issues). Complications are related to the extent of the organ involvement and severity of the blood issues. It is unclear whether KLA is a lymphatic malformation or a vascular tumor.

Treatment and Management

Should my child receive treatment for a lymphatic malformation?

All children with lymphatic malformations should complete an evaluation by a doctor who has experience with vascular malformations. Treatment plans must be made on an individual basis.

How are lymphatic malformations managed?

There is no “cure” for lymphatic malformations. Management depends on the depth, location, and extent of the malformation. A variety of treatments are used.

Treatment options include:

Observation. Small malformations are observed without treatment

Compression therapy. This involves wearing a tight-fitting garment on the affected body part to prevent pain or growth of the malformation.

Sclerotherapy. This procedure involves putting a medication directly into the malformation to shrink the problematic lymphatic channels.

Drug therapy. Medication therapy may be used to treat various symptoms and complications of lymphatic malformations.

Topical sirolimus: This medication is an ointment, cream, or gel. It is applied on lymphatic blebs.

Oral sirolimus: This medication is taken by mouth. Oral sirolimus is generally used to help manage large or complicated malformations.

Zoledronic acid (Zometa): This medication is given as an intravenous (IV) medication. Zometa is used to treat problematic bony lesions..

Surgical excision. Some small lesions may be completely surgically removed. Surgical treatment for bigger lesions may only remove a part of the lesion.

Laser therapy. This procedure uses special light beams to treat bleeding or leaking lymphatic blebs.

Are there any risks associated with treatment?

Each of these treatment options has potential side effects:

Sclerotherapy. Blistering, scarring, infection, numbness or tissue loss may occur. The malformation may shrink but then reappear or grow over time. Or the malformation may not respond to sclerotherapy treatment at all.

Drug therapy.

Topical sirolimus: There is a small risk of systemic absorption, particularly if not used as directed. Topical sirolimus may cause skin irritation.

Oral sirolimus: Before starting, your doctor will review all side effects of this medication.

Zoledronic acid (Zometa): Before starting, your doctor will review all side effects of this medication.

Surgical excision. Some scarring will occur with surgical removal of the malformation. Surgical excision may cause damage to structures involved with the lesion such as nerves, normal blood vessels, and muscle. Any left-over malformation may enlarge over time.