Figure 3. 33-year-old male non-smoker with a well differentiated type B adenocarcinoma (8 mmx9 mm) in the apical segment of the left lower lobe, with lepidic growth pattern. (a) Low dose CT shows a small, faint lesion (arrow). (b) High resolution CT shows a heterogeneous, low attenuation nodule (arrow). (c) Histopathological examination shows alveolar lining tumour growth with scattered foci of alveolar collapse (H&E stain; original magnificationx1.25). (d) Close-up view of the posteroanterior chest radiograph shows no evidence of the nodule in the middle zone of the left lung field.