A cystic hygroma is a growth that often occurs in the head and neck area. It is a birth defect.
A cystic hygroma occurs as the baby grows in the womb. It forms from pieces of material that carry fluid and white blood cells. This material is called embryonic lymphatic tissue.
After birth, a cystic hygroma most often looks like a soft bulge under the skin. The cyst may not be found at birth. It typically grows as the child grows. Sometimes it is not noticed until the child is older.
A common symptom is a neck growth. It may be found at birth, or discovered later in an infant after an upper respiratory tract infection (such as a cold).
Sometimes, a cystic hygroma is seen using a pregnancy ultrasound when the baby is still in the womb. This can mean that the baby has a chromosomal problem or other birth defects.
The following tests may be done:
If the condition is detected during a pregnancy ultrasound, other ultrasound tests or amniocentesis may be recommended.
Treatment involves removing all of the abnormal tissue. However, cystic hygromas can often grow, making it impossible to remove all of the tissue.
Other treatments have been tried with only limited success. These include:
The outlook is good if surgery can totally remove the abnormal tissue. In cases where complete removal is not possible, the cystic hygroma commonly returns.
The long-term outcome may also depend on what other chromosomal abnormalities or birth defects, if any, are present.
Complications may include:
If you notice a lump in your neck or your child's neck, call your health care provider.
Reviewed By: Josef Shargorodsky, MD, MPH, Johns Hopkins University School of Medicine, Baltimore, MD. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.