Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest provided . There is an ___ x 15 mm nodular opacity projecting over the left ninth posterior rib adjacent to the left heart border in the left lower lung . When comparison is made with the prior PET - CT , this finding likely corresponds with a prominent left nipple shadow . This is confirmed on the lateral projection . Lungs are otherwise clear . No effusion or pneumothorax is seen . Cardiomediastinal silhouette appears normal . Bony structures are intact . No free air below the right hemidiaphragm .
    OUTPUT:
    
Nodular opacity projecting over the left lower lung most likely reflects a prominent nipple shadow . Otherwise unremarkable exam .