Initial chest computed tomography. (A) Preoperative chest computed tomography (CT) demonstrates a 30-mm mass shadow (arrows) in the right upper lobe, and the distance between the tumor and the entrance of the upper bronchus is 20 mm. (B, C) Compensatory hypertrophy of the middle lobe and elevation of the right diaphragm (arrowheads), reducing the size of the thorax. Dotted arrow revealed interlobar fissure between right upper and middle lobe. RUL, right upper lobe, RML, right middle lobe.