Lung Cancers with Cystic Airspaces - an Overview.

There is increased recognition that some lung cancers arise from or are associated with air-filled cystic spaces. Recognition of precursors is important because these are often overlooked and because some of these cancers progress rapidly once a solid component develops. A systematic review suggests that such precursors typically appear as irregular air cysts; these should be distinguished from bullae and smooth round cysts with paper-thin walls that are often seen incidentally with increasing age. Such irregular cysts usually enlarge slowly before developing a ground glass or small solid component or becoming multiloculated. Such change warrants careful surveillance; continued progression of a solid component justifies intervention. Early intervention is associated with good outcomes; survival markedly diminishes if resection occurs when a more substantial solid component has developed.