Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac silhouette size is normal . The mediastinal and hilar contours are unremarkable . The pulmonary vascularity is not engorged . The lungs are clear . No pleural effusion or pneumothorax is identified . There are mild degenerative changes in the thoracic spine . The patient is status post right mastectomy .
    OUTPUT:
    
No acute cardiopulmonary abnormality .