Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lungs are well expanded . Mediastinal contours , hila , and moderate cardiomegaly are unchanged from ___ . Subtle opacity silhouetting the right hemidiaphragm seen better on lateral view is more apparent than on ___ . No pulmonary edema , pleural effusion , or pneumothorax .
    OUTPUT:
    
Subtle right lower lobe opacity could represent pneumonia .