Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac , mediastinal and hilar contours show substantial decrease in a left hilar mass . This suggests a positive treatment response although bulging character to the aortopulmonary window is concerning for residual tumor or metastatic lymphadenopathy . The lungs appear otherwise clear .
    OUTPUT:
    
Marked decrease in left hilar mass . No evidence of acute cardiopulmonary disease .