Newborn with a large left chest wall deformity

CXR and CT of mesenchymal hamartoma of chest wall
CXR AP shows a large mass arising from the left 4th-6th ribs. Axial CT without contrast of the chest with soft tissue windows (right upper and middle) show the mass to have a fluid-fluid level within it superiorly while bone windows (right lower) show the mass to be calcified.

The diagnosis was mesenchymal hamartoma of the chest wall.