Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest provided . Subtle increased opacity at the right medial lung base could represent an early pneumonia in the correct clinical setting . Lungs are otherwise clear . No large effusion or pneumothorax . The heart remains mildly enlarged . Mediastinal contour is stable . Bony structures are intact .
    OUTPUT:
    
Subtle opacity at the right medial lung base may represent a very early right middle lobe pneumonia .