Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is notable interval improvement in the right pleural effusion . There is a dense opacification with a rounded contour below the aerated right residual lung . Though the contour has the appearance of an elevated right hemidiaphragm , this appears to represent a large subpulmonic effusion when compared to ___ chest CT . There is improved aeration of the right lung with residual opacifications likely representing combination of atelectasis and known malignancy ; can not exclude superimposed infectious process . Atelectatic changes are noted within the left lower lung with a slightly greater degree of collapse in the posterior medial subsegment . Small left pleural effusion identified . Abnormal contour of the right upper mediastinum is consistent with known malignancy . Left - sided cardiomediastinal borders are unremarkable .
    OUTPUT:
    
Interval mild improvement in right pleural effusion with likely a large residual subpulmonic pleural effusion . Dense opacifications in the now apparent right residual lung likely represents a combination of atelectasis and known malignancy . Small left pleural effusion .