CPAM cannot be made because of the normal response of the lung to inflammation and abscesses, i.e. repair by fibrosis and epithelisation of healed abscesses with columnar-to- pseudostratified columnar epithelium. CPAM type 1 is amenable to surgical resection with good long-term survival (in the absence of a rarely occurring severe associated anomaly). CPAM type 2 CPAM type 2 is composed of cysts 0.5–2.0 cm in diameter that resemble bronchioles. The clinical picture is often dictated by the occurrence, in y50% of cases, of other severe anomalies (sirenomelia, renal agenesis/dysgenesis, diaphragmatic hernia and cardiovascular). When an isolated lesion, it may be seen in the first month of life as mild- to-severe respiratory distress. Radiographically, the lesion may be difficult to visualise as most lesions exhibit cysts of only 0.5–1.0 cm in diameter. Grossly, the lesions are smaller than other CPAM lesions and blend with the adjacent Fig. 4. – Congenital pulmonary airway malformation type 1. In y35–40% of cases, clusters of mucogenic cells: a, b) lie along the surface of the cysts or c, d) fill small alveolar duct-like structures. a, c) haematoxylin and eosin stain b) alcian blue and d) mucicarmine. J.T. STOCKER, A.N. HUSAIN 8