Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Curvilinear opacity in the left upper lobe is mild atelectasis , terminating in the thickened upper pole of the left hilus where adenopathy was shown on recent chest CT . Right lung is clear . Pleural surfaces are normal . The cardiac and mediastinal silhouettes are unremarkable .
    OUTPUT:
    
Mild atelectasis , left upper lobe attributable to previously demonstrated left hilar mass . No pneumonia or evidence of cardiac decompensation .