What abnormality demonstrated on this radiograph?
There is a mass lesion laterally within the left upper lobe (adjacent to the oblique fissure on the lateral view).
What specific imaging characteristic will help to narrow the differential diagnosis?
There is cavitation and an air-fluid level.
There is a large cavitating mass in the left upper lobe adjacent to the oblique fissure. The prominent air-fluid level is best seen on the lateral radiograph.