Sonomorphology of a bronchioloalveolar cell carcinoma in a flooded human lung lobe. ( a ) Sonogram of a homogeneous tumour with respect to bronchi and blood vessels. The tumour is slightly hyperechoic compared to surrounding normal lung tissue, making differentiation difficult (arrows mark the border between tumour on the left and normal lung tissue on the right). ( b ) Macroscopic specimen (cut through the tumour after sonographic examination). Tumour border was marked with arrows. The tumour presents as a light grey mass in the right of the photograph.