Abstract
Ewing's sarcoma (ES) is the second most common osseous tumor in young patients after osteosarcoma. All primitive neuroectodermal tumors (PNET) and Askin tumors are members of Ewing's sarcoma family of tumors (ESFT), which all have aberrant translocations between the 11th and 22nd chromosomes. Only one in five cases of Ewing's sarcoma occurs as extraskeletal. In this report, we describe a young female with a palpable lump on her spine who presented with paravertebral and thoracic extraskeletal Ewing's sarcoma (EES). Over six months, the swelling gradually increased in size, and the patient reported episodes of episodic pain and fever. Examining the swelling, a non-reducible, non-tender ovoid lump measuring approximately 8 cm x 5 cm was found to have smooth margins and be slightly mobile. The use of magnetic resonance imaging (MRI) helped diagnose, plan surgical resections, assess neoadjuvant chemotherapy effectiveness, and detect local recurrences and metastatic spread of the tumor. The differential diagnosis of EES included embryonal rhabdomyosarcoma and lymphoma. The use of immunohistochemical markers further differentiated the diagnoses. In conclusion, it should be noted that EES, though rare, should be considered when evaluating soft tissue lumps of neoplastic characteristics, in children or adolescents. Considering the poor prognosis of this disease, early detection is essential. The MRI plays a vital role in diagnosing cancer, staging it locally, assessing response to neoadjuvant therapy, and identifying local recurrences and metastases.