Thoracic Ewing sarcoma (Askin tumor) presenting with severe respiratory distress in a four-year-old child: a case report

Abstract

Ewing sarcoma is an aggressive malignant small round cell tumor that primarily affects children and adolescents. Thoracic involvement, known as Askin tumor, represents a rare variant arising from the chest wall and may mimic infectious or mediastinal pathologies, often leading to delayed diagnosis. We report the case of a four-year-old female child who presented with progressive left-sided chest wall swelling and severe respiratory distress. Imaging revealed a large soft-tissue mass occupying the left hemithorax with rib destruction and mediastinal shift. Histopathological confirmation was challenging due to inadequate core biopsy sampling; however, fine-needle aspiration cytology suggested a small round cell tumor consistent with Ewing sarcoma. Given the patient’s critical clinical condition, neoadjuvant chemotherapy was initiated based on clinicoradiological and cytological findings. Following initiation of chemotherapy with vincristine, doxorubicin, and cyclophosphamide, the child demonstrated rapid clinical stabilization and significant improvement in respiratory distress. This case highlights the diagnostic challenges of thoracic Ewing sarcoma in critically ill pediatric patients and underscores the importance of early imaging, pragmatic diagnostic strategies, and prompt initiation of multimodal therapy.