title: Congenital cystic adenomatoid malformation of the lung (CCAM): evaluation of the cellular components.
abstract: Congenital cystic adenomatoid malformation of the lung (CCAM) is a rare congenital lesion whose pathogenesis is not well defined. It is generally accepted that the various types of CCAMs originate at different levels of the tracheobronchial tree. To further define the pathogenesis of CCAM, we evaluated the cellular composition of different CCAM types by immunohistochemistry. Twenty-two CCAMs (17 CCAM type 1, two type 2, one type 3, and two type 4) were collected. The cellular composition was determined using immunohistochemical stains for type I cell-associated antigen (T1 cell-Ag), surfactant proteins and surfactant protein precursors (SP-A, SP-B, proSP-B, and proSP-C), neuroendocrine cells (GRP), Clara cells (UP-1), and the adhesion molecule CD44v6, a glycoprotein thought to be involved in cell-matrix and cell-cell interactions. Eleven fetal lungs also were analyzed to compare cytodifferentiation of the epithelial-lined cysts of the different types of CCAM with the stages of normal lung development. Our results indicate that CCAM is caused by an arrest in lung development, and, on the basis of cytodifferentiation, two major subtypes can be distinguished. One subtype consisting of CCAM types 1, 2, and 3 that shows a bronchiolar type of epithelium and a second subtype, consisting of CCAM type 4, that has an acinar-alveolar type of epithelium. Our findings also suggest that these two subtypes may arise at different stages of the branching of the bronchopulmonary tree, the first at the pseudoglandular stage and the second at the saccular stage.
authors.affiliation: Department of Pathology, New York University Medical Center, NY 10016, USA.
authors.forename: R A
authors.initials: RA
authors.lastname: Morotti
authors.forename: J
authors.initials: J
authors.lastname: Cangiarella
authors.forename: M C
authors.initials: MC
authors.lastname: Gutierrez
authors.forename: J
authors.initials: J
authors.lastname: Jagirdar
authors.forename: F
authors.initials: F
authors.lastname: Askin
authors.forename: G
authors.initials: G
authors.lastname: Singh
authors.forename: S A
authors.initials: SA
authors.lastname: Profitt
authors.forename: S E
authors.initials: SE
authors.lastname: Wert
authors.forename: J A
authors.initials: JA
authors.lastname: Whitsett
authors.forename: M A
authors.initials: MA
authors.lastname: Greco
mesh_terms: D000951:Antigens, Neoplasm / Q000378:metabolism; D018956:CD5 Antigens / Q000378:metabolism; D015615:Cystic Adenomatoid Malformation of Lung, Congenital / Q000378:metabolism / Q000473:pathology*; D005315:Fetal Diseases / Q000378:metabolism / Q000473:pathology*; D005333:Fetus / Q000002:abnormalities* / Q000378:metabolism / Q000473:pathology; D019886:Gastrin-Releasing Peptide / Q000378:metabolism; D006023:Glycoproteins / Q000378:metabolism; D006801:Humans; D018960:Hyaluronan Receptors / Q000378:metabolism; D009363:Neoplasm Proteins / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D011498:Protein Precursors / Q000378:metabolism; D011510:Proteolipids / Q000378:metabolism; D037721:Pulmonary Surfactant-Associated Protein C; D011663:Pulmonary Surfactants / Q000378:metabolism; D013501:Surface-Active Agents / Q000378:metabolism
chemical_list: D000951:Antigens, Neoplasm; C112697:CD44v6 antigen; D018956:CD5 Antigens; C084391:Clara cell antigen; D006023:Glycoproteins; D018960:Hyaluronan Receptors; D009363:Neoplasm Proteins; D010455:Peptides; D011498:Protein Precursors; D011510:Proteolipids; D037721:Pulmonary Surfactant-Associated Protein C; D011663:Pulmonary Surfactants; C489679:SFTPC protein, human; D013501:Surface-Active Agents; C105511:surfactant protein B propeptide; D019886:Gastrin-Releasing Peptide