Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared with prior radiographs on ___ , and has been interval decrease in size of a left - sided pleural effusion . Left pleural drain is stable in position . Right lung is clear without consolidation , effusion or pneumothorax . A left apical mass is better assessed on CTA on ___ . The cardiomediastinal silhouette is unchanged .
    OUTPUT:
    
Interval decrease in left - sided pleural effusion .