Ewing Sarcoma Misdiagnosed as a Traumatic Hematoma: A Case from Family Practice

BACKGROUND Timely diagnosis of cancers is crucial, as delays can adversely affect a patient's outcome and experience. Since soft tissue hematoma is a common clinical condition following trauma, soft tissue tumors can be misdiagnosed as hematomas due to the similar clinical features. CASE REPORT A 13-year-old girl presented with a gradually expanding swelling in the left arm that developed following minor trauma. She was seen by several general practitioners, and the swelling was managed as a soft tissue hematoma with the application of ice packs and compression, which did not result in any improvement. The initial plain radiograph of the left humerus revealed a large soft tissue swelling with areas of calcifications and minimal periosteal changes. The swelling was further evaluated by ultrasound, showing a hypoechoic lesion with internal septation and increased vascularity. These findings were mistakenly interpreted as a traumatic hematoma. Considering the prolonged duration and the progressive nature of the condition, the patient was referred for magnetic resonance imaging, which showed a soft tissue lesion involving the humeral shaft and sparing the proximal and distal epiphyses. An ultrasound-guided biopsy confirmed the diagnosis of Ewing sarcoma. CONCLUSIONS Ewing sarcoma may present with a clinical picture similar to that of a traumatic hematoma. Hence, this case highlights the need for considering soft tissue tumors as a differential diagnosis in patients presenting with an expanding swelling. Primary care physicians should have a high index of suspicion for malignancies and should not be reluctant to refer patients for further investigations in cases exhibiting an unusual course of the clinical condition.