Figure 1

Adenocarcinoma in situ, non-mucinous type. (a) A persistent ground-glass opacity resulting in a surgical wedge excision whose cut surface is shown in panel b. (c) Preserved irregularly inflated alveolar architecture, and at the arrow normal pulmonary vasculature. (d) The cuboidal, relatively uniform neoplastic cell population lining thickened but otherwise preserved alveolar walls. ((a) CT scan, (c, d) H&E sections, original magnification × 10 and × 150).