Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There has been interval improvement of the mild bilateral pulmonary edema , predominantly in the right upper and lower lobes , with a persistent opacity at the right lung base , consistent with pneumonia . The cardiomediastinal silhouette is normal . Mild emphysematous changes are persistent . There is no evidence of pneumothorax . The visualized osseous structures are unremarkable .
    OUTPUT:
    
1 . Interval improvement of mild pulmonary edema . 2 . Persistent right lower lung opacity secondary to pneumonia , however follow up to resolution with chest CT is recommended to exclude malignancy .