Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single portable semi supine AP radiograph demonstrates abnormal contour involving the pulmonary arterial window either enlarged left pulmonary artery or adenopathy . Heart size is upper limits of normal . No evidence of pulmonary edema . No focal consolidation convincing for pneumonia is present . There is no pleural effusion or evidence of pneumothorax . Imaged osseous structures and upper abdomen are without an acute abnormality .
    OUTPUT:
    
Prominence of the left pulmonary arterial window may reflect enlarged pulmonary artery or alternatively adenopathy . No focal opacity convincing for pneumonia .