Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: As compared to ___ , there has been mild interval improvement in the aeration of the left upper lobe . Redemonstrated is a left upper lobe mass , as well as findings of post obstructive atelectasis . Lung volumes remain somewhat reduced , resulting in the appearance of vascular congestion . A small pleural effusion is seen on the left . There is no evidence of pneumothorax or pulmonary edema . The heart size is stable . The mediastinal contours are normal . No bony abnormalities are detected .
    OUTPUT:
    
1 . No evidence of acute fracture or hemothorax . 2 . Stable appearance of a left upper lobe mass , with adjacent atelectasis . 3 . Small left - sided pleural effusion .