Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A subtle 3 .3 cm diameter rounded cystic lesion is present in the left infrahilar region , corresponding to a focal abnormality in the superior segment left lower lobe detected on recent CT thoracic spine study of one day earlier . Lungs are otherwise clear except for a small calcified granuloma in the left lower lobe . There are no pleural effusions or acute skeletal findings .
    OUTPUT:
    
Left lower lobe superior segment lesion corresponds to an abnormality on recent CT thoracic spine of one day earlier . Although possibly due to a nodular focus of consolidation from aspiration or contusion , followup radiographs are recommended in six to eight weeks to document resolution . If this fails to resolve radiographically , a followup CT would be recommended , as the differential diagnosis for this finding includes lung adenocarcinoma .