Treatment involves complete removal of the abnormal tissue whenever possible. However, cystic hygromas can often invade other neck structures, making this impossible.

Other treatments have been attempted with only limited success. These include:

• Chemotherapy medications
• Injection of sclerosing medications
• Radiation therapy
• Steroids

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 outcome may also depend on what other chromosomal abnormalities or birth defects, if any, are present.

Complications may include:

• Bleeding
• Damage to structures in the neck caused by surgery
• Infection
• Return of the cystic hygroma

If you notice a lump in your neck or your child's neck, call your doctor.