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 . Relative lucency of right lung field is likely due to mastectomy . No pleural effusion or pneumothorax is evident . Stable elevation of left hemidiaphragm . Degenerative changes are noted in the thoracic spine .
    OUTPUT:
    
No acute intrathoracic process .