Masses (or cysts) that appear in the lungs have one of two common causes. In adults, they are usually caused by malignancies or infections. In children, they are more typically genetic malformations present at birth.
One such condition that occurs in approximately 1 of every 30,000 births, is congenital pulmonary airway malformation (CPAM), previously known as congenital cystic adenomatoid malformation. CPAM is a rare condition in which abnormal tissue forms in large parts of the chest cavity instead of healthy, working lung tissue.
Children with this rare developmental anomaly may experience respiratory distress at birth or may have no symptoms until adulthood. The condition is usually detected during prenatal ultrasounds.
Surgical removal is usually the most successful treatment.