Histology of type 2 congenital pulmonary airway malformation (CPAM)

Histologic specimen of a type 2 congenital pulmonary airway malformation (CPAM). The lesion is composed of structures resembling terminal bronchioles and is lined by low columnar to cuboidal epithelium. These structures are separated by small amounts of connective tissue. In this example, alveolar structures are not apparent.