Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A large right pleural effusion is similar to ___ , allowing for difference in modality . There is adjacent compressive atelectasis and leftward shift of the normally midline mediastinal structures . Retrocardiac opacity may represent atelectasis or consolidation . No pneumothorax . No radiopaque foreign body .
    OUTPUT:
    
Large right pleural effusion , similar to ___ , with compressive atelectasis and leftward mediastinal shift . Retrocardiac opacity may represent atelectasis but pneumonia is not excluded in the appropriate clinical setting .