Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Linear opacity at the left lung base is likely atelectasis . There is a 1 cm nodule projecting over the left lung apex . Lungs are otherwise clear . There is no pneumothorax . Cardiomediastinal silhouette is within normal limits . Lateral left clavicular fracture is partially visualized , better seen on concurrent shoulder films .
    OUTPUT:
    
No acute cardiopulmonary process . A 1 cm left upper lobe nodular opacity for which apical lordotic views are suggested for further evaluation regarding the possibility of a pulmonary nodule and if it persists , CT scan will be necessary .