Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac , mediastinal and hilar contours appear unchanged including cardiac enlargement . There has been marked increase in a right - sided pleural effusion , which is now very large . Although there is probably coinciding atelectasis of much or all of the right lower lobe , as well as the right middle lobe , there is also leftward shift of mediastinal structures that has increased . There is no pleural effusion on the left .
    OUTPUT:
    
Large right - sided pleural effusion , substantially increased .