Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Subtle 1 cm ovoid opacity projecting over the posterior right sixth rib may be due to overlap of structures however , recommend a shallow oblique radiographs to exclude underlying lesion . The left lung is clear . There is persistent slight blunting of the bilateral costophrenic angles . No pulmonary edema is seen . The cardiac and mediastinal silhouettes are stable .
    OUTPUT:
    
Subtle 1 cm ovoid opacity appears to project over the posterior right sixth rib may be due to overlap of structures however , recommend shallow oblique radiographs to exclude underlying lesion .