RESUMEN
Congenital cystic adenomatoid malformation (CCAM) of the lung is an uncommon embryonic developmental anomaly, characterized by the presence of one or multiple interconnecting cysts. This disease may present various clinical aspects, stillborn or perinatal death, respiratory distress in newborns, and acute and chronic pulmonary infections in older infant and children. We experienced a case of CCAM in a 3-years, 8-month-old male who had frequent upper respiratory tract infection and recurrent pneumonia. Chest X-ray and chest CT showed a cavitary lesion in the right middle lobe. Histologic examination revealed numerous small and large sized cysts in the parenchyma. The large cysts were mainly lined by pseudostratified ciliated cells and the small cysts are lined by simple cuboidal cells and subclassified Stocker type mixed I and II. Wedge resection was done with satisfactory postoperative courses clinically and radiologically. We report a case of CCAM (I and II mixed type) with a brief review.