Slide 1: Where is the 5cm mass on this CXR?

Slide 2: A1: The mass is in the mediastinum? Q2: What test could we do to better visualize the mass?

Slide 3: A2: A chest CT with contrast confirms an anterior mediastinal mass. Q3: why are mediastinal masses so hard to see on plain X-rays?

Slide 4: Visualization of soft tissue masses on CXR. Soft tissue masses are (usually) EASY TO SEE on a background of normal black air-filled lungs. Ddx: broad and depends on appearance. Includes malignancy, infection, benign tumors, vascular, inflammatory.

Soft tissue density mediastinal masses blend in with the normal soft tissues of the mediastinum. Ddx: depends on the compartment! Anterior: thyme mass, germ cell tumor, lymphoma, thyroid. Middle: lymphadenopathy, cystic tumor, aneurysm, esophageal tumor. Posterior: neurogenic, meningocele, thoracic spine lesions.