Congenital cystic adenomatoid malformation with partial anomalous pulmonary venous return


Imaging findings are pathognomonic. 

A multiloculated cystic lung mass in a young patient, which conforms to a type 1 congenital pulmonary airway malformation.

Anomalous drainage of pulmonary veins into the systemic veins, in this case, from left upper lung to left brachiocephalic vein.