Congenital pulmonary airway malformation

What it means

Congenital pulmonary airway malformation (CPAM) - previously known as congenital cystic adenomatoid malformation (CCAM) - is a relatively rare developmental malformation of the lower respiratory tract. It is a hamartomatous, dysplastic developmental abnormality of the lung characterized by abnormal airway patterning during lung branching morphogenesis and is formed by abnormal branching of the immature bronchioles.

The term CPAM has been recommended as being preferable to the term congenital cystic adenomatoid malformation, since the lesions are cystic or adenomatoid in only a limited number of cases. Only three types of CPAMs are distinguished at imaging: large cyst CPAM (type I) and small cyst CPAM (type II), which constitute macrocystic CPAMs; and microcystic or solid type (type III) lesions, which have cysts that are smaller than 5 mm in diameter, with no discernible cystic spaces.

Rare diseases that can present with this1

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: CCAM · Congenital cystic adenomatoid malformation · Congenital cystic adenomatoid malformation of the lung · Congenital cystic disease of the lung · Cystic adenomatoid lung disease