The chest X-ray shows typical findings of right upper lobe atelectasis, with upward and medial displacement of the horizontal (minor) fissure and displacement of the trachea toward the atelectatic lung. CT confirms atelectasis and shows the endobronchial lesion which most likely represents lung cancer. Intravenous contrast may have been helpful in differentiating atelectatic lung and hilar mass, but was not given in this case.