Fig. 3.

Progression at the 1-year interval of a non-solid nodule in a 66-year-old woman. (a) Low-dose CT section shows a 12-mm nodule with ground-glass attenuation of the upper left lobe (arrow). (b) CT scan obtained at annual repeat LDCT demonstrates a substantial stability in size but with increased density, that indicates an increased risk for malignancy. The lesion was surgically removed with a diagnosis of lung adenocarcinoma. Sub-solid nodules that show an increment in attenuation should be considered suspicious for malignancy