Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest were reviewed . A large right mid lung opacification extends anteriorly from the hila to the anterolateral chest wall . The left lung is clear . The heart size is normal and there is no evidence of vascular congestion , pleural effusion or pneumothorax . There are no concerning osseous or soft tissue lesions .
    OUTPUT:
    
Large right mid lung opacification could be postobstructive pneumonia or a mass . CT would be necessary for full evaluation of a possible underlying lesion however an alternative would be to treat for three to four weeks to see if there is clearing .