Rare and Complex Lymphatic Anomalies

Rare and Complex Lymphatic Anomalies are rare, progressive disorders of the lymphatic system.

Most of these Lymphatic Anomalies are present from birth. But signs and symptoms can emerge later. They are typically present before the age of 20. The condition is often under-recognised in adults.

Because the diseases can affect different parts of the body, symptoms can vary depending on which body areas are affected. Unfortunately, every patient is unique and has their own challenges.


Lymphatic malformations often occur in the skin and soft tissue. They contain lymphatic fluid and are seen as a “mass” or cyst, that may be composed of large (macrocystic) or small (microcystic) lesions.

When the draining of lymphatic fluid does not occur properly, a more generalized swelling occurs. This is due to accumulation of lymphatic fluid within healthy tissues. This is called lymphedema and is most commonly seen in feet and legs, but can be present in hands, arms and even the face.


Both types of swellings can produce pain due to the increase in the amount of lymph fluid in the tissue (in case of lymphedema), or due to increased lymph fluid, bleeding and/or infection (in case of lymphatic malformation).  Symptoms and risks related to sudden swellings in the malformations due to bleeding, inflammations or infections are highly dependent on the involvement of vital systems in the body.

Internal lymphatic leakage

When the lymphatic malformation occurs in the chest, it can cause fluid accumulation around the heart and lungs leading to wheezing, coughing and feeling short of breath.

Chylous effusions (accumulation of lymphatic fluids made up of fat, water and lymphocytes) are often seen. There can be spontaneous drainage either externally (leakage from the skin) or from one internal compartment to another. If the lung cavity or belly fills with fluid there can be significant or even life-threatening problems.

When the lymphatic malformation is in the belly, it can develop fluid effusions or cysts, as well as protein-losing enteropathy, producing abdominal swelling, pain and/or diarrhoea.

It is known that children with Noonan syndrome (an inherited syndrome) have an increased risk of developing a CCLA.

Fractures and bone pain

Bone pain and fractures can occur in any patient with a Complex Lymphatic Anomaly. However, recurrent fractures, extensive lesions in the bone and persistent pain are the most frequent symptoms in Gorham Stout Disease.

After Michio Ozeki, Toshiyuki Fukoa, 2019.

The International Society for the Study of Vascular Anomalies (ISSVA) has made a complete classification of lymphatic and other vascular malformations. Read more