Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size and mediastinal contours are normal . Left upper lobe volume loss is present , manifested by upward retraction of the left hilum , and accompanied by asymmetrical left apical thickening . Lungs and pleural surfaces are otherwise clear , and there are no pleural effusions or acute skeletal findings .
    OUTPUT:
    
Left upper lobe volume loss with associated asymmetrical left apical thickening , likely the sequela of previous infection in the absence of previous history of radiation therapy . Direct comparison to any outside radiographs would be helpful to determine retrospective stability of this appearance . If unavailable , short - term followup radiographs in three to six months may be helpful to confirm stability .