Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared to prior there is a new moderate to large left pleural effusion with associated left basilar opacity . The right lung is grossly clear . Right chest wall Port - A - Cath ends at the cavoatrial junction . There is no pneumothorax .
    OUTPUT:
    
Moderate to large left pleural effusion with associated atelectasis , a concurrent underlying left lower lobe pneumonia can not be excluded .