What are Lymphatic Malformations

Lymphatic malformations are rare, non-cancerous growths caused by the abnormal development of the lymphatic system, which typically manifest as fluid-filled sacs or cysts. These lesions occur when lymphatic vessels fail to drain properly, leading to swelling that can affect any part of the body, most commonly the head and neck region.

What causes lymphatic malformations?

Lymphatic malformations arise during fetal development due to errors in the formation of lymphatic channels. Unlike typical veins or arteries, these malformed vessels do not connect correctly to the rest of the circulatory system, causing lymphatic fluid to pool in localized areas. These are distinct from hemangiomas, as lymphatic malformations are congenital malformations rather than tumors of blood vessels, meaning they generally grow in proportion to the child rather than undergoing a rapid phase of proliferation.

How are lymphatic malformations classified?

Clinicians classify lymphatic malformations based on the size of the fluid-filled spaces seen on imaging:

• Microcystic: Composed of many tiny, small cysts; these often appear as clusters of small, fluid-filled bubbles on the skin.


• Macrocystic: Characterized by larger, easily visible fluid-filled sacs.


• Mixed: A combination of both small and large cysts within the same lesion.

Who is affected by lymphatic malformations?

Lymphatic malformations are rare, with an estimated prevalence of approximately 1 in 2,000 to 4,000 live births. They affect males and females equally and show no specific geographic or ethnic predisposition. While they are present at birth, they may not become clinically apparent until childhood or early adulthood, often triggered by an infection or trauma that causes the cysts to fill rapidly with fluid.

How do lymphatic malformations differ from other conditions?

It is important to distinguish lymphatic malformations from vascular tumors. While vascular tumors are characterized by rapid cell growth, lymphatic malformations are stable, structural abnormalities. At DiseaseMaps.org, 11 community members have shared their experiences, highlighting the importance of specialized multidisciplinary care, as these malformations can impact breathing, swallowing, or vision depending on their location.

Next steps

• Consult with a vascular anomalies specialist or an interventional radiologist.


• Undergo diagnostic imaging, such as an MRI, to map the extent of the malformation.


• Join a patient support group to connect with others navigating similar challenges.


• Monitor for signs of infection or sudden swelling, which require prompt medical evaluation.

Medical disclaimer: This content is for educational purposes only and does not constitute professional medical advice, diagnosis, or treatment; always seek the advice of your physician or other qualified health provider with any questions regarding a medical condition.

References

• NIH Genetic and Rare Diseases Information Center (GARD)


• Orphanet: Portal for rare diseases and orphan drugs


• International Society for the Study of Vascular Anomalies (ISSVA) Classification


• OMIM (Online Mendelian Inheritance in Man)