Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral chest radiographs demonstrate unremarkable cardiomediastinal and hilar contours . Lungs are clear . Hyperdense rounded opacity in the apical portion of the left lung projecting over the left clavicle is of unclear etiology . No pleural effusion or pneumothorax identified .
    OUTPUT:
    
Round density rpojects over the left apex , slightly increased in conspicuity - recommend nonemergent CT to assess further .