Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest were provided . There is subtle nodular retrocardiac opacity seen only on the lateral view which could indicate a very early lower lobe pneumonia . Please note no definite consolidation on the frontal view is visualized . No effusion or pneumothorax . Cardiomediastinal silhouette is normal . Bony structure is intact .
    OUTPUT:
    
Subtle nodular retrocardiac opacity , which in the correct clinical setting could represent a lower lobe pneumonia .