Fatal complications in a young adult with large Ewing sarcoma of the chest wall.

Ewing sarcoma is an aggressive bone and soft tissue malignancy arising predominantly in children and young adults, with a peak incidence at 15 years of age with a slight male predominance. The ribs are a recognized primary site of Ewing sarcoma, accounting for approximately 10% of cases. Tumors arising from the ribs/chest wall, often called Askin tumors, are the most common primary malignant chest wall tumor in children and young adults. These tumors are highly aggressive, often presenting with early micrometastatic disease and requiring prompt multimodal therapy. We present the case of a 20-year-old female with an exceptionally large Ewing sarcoma of the anterior chest wall, likely originating from the rib, who was lost to follow-up after initial presentation 20 months earlier. On re-presentation, imaging demonstrated extensive progression of disease with invasion of the breast, lung, and chest wall, as well as widespread metastatic disease including vertebral involvement with pathologic compression fractures and spinal cord compression. Despite initiation of multimodal therapy with chemoradiation, her clinical course was complicated by pleural effusions, hydropneumothorax, and progressive tumor necrosis. She ultimately developed acute respiratory distress syndrome (ARDS) following palliative surgical resection and passed away from her disease approximately three years after initial presentation. This case highlights the aggressive natural history of a chest wall Ewing sarcoma, and the role of imaging in identifying disease extent, complications, and progression.