Teenager with an enlarging, tender anterior chest wall mass Pediatric Imaging Chest January 17, 2019December 20, 2021 Axial CT without contrast of the chest shows an anterior mediastinal mass compressing the airway leading to left lower lobe atelectasis and eroding the sternum with periosteal reaction. The diagnosis was Hodgkin lymphoma. Related Published January 17, 2019December 20, 2021