Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . Cardiac , mediastinal and hilar contours appear stable . There is a very small pleural effusion on the right and a small one on the left with associated opacity , probably atelectasis . Posterior left basilar opacification has increased somewhat ; infectious process is not excluded . Port - A - Cath appears unchanged .
    OUTPUT:
    
Increasing left posterior basilar opacity , compatible with pleural effusion and atelectasis but not specific . No free air identified .