Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac size is normal . The aorta is tortuous . In the retroesternal space there is a 5 mm nodule that needs further evaluation with CT . Otherwise the lungs are clear . Mild degenerative changes in the thoracic spine . There is no pleural effusion
    OUTPUT:
    
Lung nodule . CT is recommended for further evaluation