Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Right - sided PleurX projects in mid hemithorax . Compared to the previous exam , the pneumothorax has decreased in size from 5 .1 to 3 .5 cm . As shown on yesterday PET - CT , there is almost no more pleural effusion left on that side to drain . The increased density of the right lung is mainly explained by the large lung lesion with subsequent atelectasis of right upper lobe and right middle lobe . The left lung is unremarkable and the left pleural effusion is small .
    OUTPUT:
    
Patient is known with right lung mass with subsequent atelectasis . Right apical pneumothorax has decreased in size and is now moderate . As shown on previous PET - CT , there is almost no more pleural effusion to drain .