Lung cancer. This 76 year old has a long history of smoking – note the evidence of emphysema (hyperinflated, lucent lungs with flattened diaphragms). There is a 3 cm mass with spiculated margins in the right lung (circled). Biopsy confirmed adenocarcinoma. This patient also happens to have a huge thoracic aortic aneurysm, which is displacing the trachea to the right.