[Congenital cystic adenomatoid malformation of the lung or congenital pulmonary airway malformation].

The cystic adenomatoid malformation of the lung is an hamartomatous lesion, easily identifiable by its morphology through the application of Stocker's et al (1977) classification (type 1, 2 and 3) and also following the criteria of Yousem, to understand the five types dependent on the level of malformation in the airway and lung. The three morphological types described by Stocker were identified in 6 cases of the archive of the Department of Pathology of Coimbra's University Hospital, studied morphologically by the use of Movat's pentachromic stain and the application of the antibody anti-CK7 and anti-body anti-TTF1. In the three morphological types the elastic alveolar net is absent. The CK7 identifies the epithelial distribution and is useful to evaluate the extension of the inflammatory lesion. The antibody anti-TTF1, apparently absent in type 3 cases, is easily identified in type 1 and 2 cases and overexpressed in inflammatory areas. It seems that the absence of cells identified by the antibody anti-TTF1 prevents overdiagnosing of type 4 in Yousem's classification of congenital pulmonary airway malformation (CPAM).