Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: In the right upper lung zone , there is an ill - defined dense opacity which correlates to the nodular opacity seen on the prior CT . In comparison to the prior chest radiograph from ___ , it appears slightly less apparent , but that may be due to patient positioning . Compared to the prior chest radiograph from ___ , it is not changed . The remainder of the lung fields is clear . There is no pleural effusion or pneumothorax . There is no pulmonary edema . The cardiomediastinal silhouette is normal .
    OUTPUT:
    
Right upper lung zone opacity . Given the appearance , it is concerning for a possible mass . Alternatively , it could be due to continued infection . Continued followup is recommended . Chest CT pending .