Case report of a patient with Ewing’s sarcoma.

Abstract

Ewing's sarcoma is the second most common bone tumor in childhood and adolescence. Its incidence varies significantly among races, but is relatively rare among black children and the Chinese population. Patients with Ewing sarcoma exhibit local symptoms characterized by tumor mass formation, pain, swelling, venous dilatation, and hyperemia. Pathological fractures due to bone metastases with progressive neurological deficit to paralysis may occur. In cases where Ewing's sarcoma originates in the chest wall, pleural infiltration combined with carcinomatous pleuritis is often presented .

We present the case of a 40-year-old patient initially diagnosed with a Baker's cyst in the left popliteal fossa. After consultation with an orthopedic surgeon, the patient was referred for surgical removal of the formation. An extirpation was performed, but the histological result did not confirm the diagnosis and characterized the finding as "cystic lobular capillary hemangioma ".  A re-excision was performed in November 2018 due to recurrence of the formation. Immunohistochemical tests performed subsequently found that immunophenotypically and morphologically the finding correlated most highly with Ewing's extraskeletal sarcoma.  Two months after excision, PT/CT was performed, which showed no recurrence and no secondary dissemination.  One year later, due to arthralgias in the right shoulder joint, the patient underwent MRI and CT.  The result of imaging studies revealed tumor recurrence in the diaphysis of the right humerus with secondary intrapulmonary dissemination. The patient was started on chemotherapy with good clinical response.