Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . There is large left retrocardiac opacity with areas of lucency which could represent a very large hiatal hernia , possibly containing bowel , not well evaluated on this study . The cardiac silhouette is enlarged ; however , this likely in part relates to the hernia . Right lung is clear . The aortic knob is calcified . No pneumothorax is seen .
    OUTPUT:
    
Large retrocardiac left mid - to - lower hemithorax opacity with areas of lucency with appearance of bowel and possibly stomach , likely related to large hernia possibly containing bowel , not well evaluated on this study , no priors for comparison . Minimal right base atelectasis .