Adenocarcinoma in the central right inferior lobe of an excised human lung. ( a ) Computed tomography scan shows a central, peribrochial tumour. ( b ) Sonography under atelectasis: the tumour appears homogenous and is poorly demarcated (isoechogenic) from lung tissue. ( c ) Sonography after flooding: homogenous tumour tissue is hypoechoic, irregularly configured with fringe-like processes, and is well-demarcated from the normal lung parenchyma. Bronchial destruction is evident (arrow).