Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Moderate loculated left - sided pleural effusion . There is adjacent rounded opacity partially imaged in the left lung . Linear opacities in the right upper lobe . The right lung is otherwise clear . No right - sided pleural effusion . No pneumothorax .
    OUTPUT:
    
Moderate left - sided effusion with adjacent rounded opacity may reflect pneumonia with parapneumonic effusion or underlying malignancy can not be excluded . CT thorax is recommended , ideally after the pleural fluid has been drained .