Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Mild focal rightward deviation of the trachea is stable , previously reported to be due to enlarged left lobe of the thyroid . Prominence of the right hilum is stable . Calcification of the aortic knob is similar in appearance as compared to ___ . Slight blunting of the posterior left costophrenic angle is stable since at least ___ and is chronic . Patchy left base retrocardiac opacity has been present over multiple prior studies dating to at least ___ and may represent scarring . The cardiac silhouette is mild to moderately enlarged . No overt pulmonary edema is seen . Projecting over the posterior left 4th rib , is a 1 .1 cm nodular opacity , which is similar in appearance compared to the radiograph from ___ , suggesting that it is benign .
    OUTPUT:
    
Grossly stable chest radiograph with perhaps slight enlargement of the cardiac silhouette , given differences in technique .