Abstract
BACKGROUND: Extraskeletal Ewing sarcoma (EES) is a member of the Ewing sarcoma family of tumors which is pathologically known as a small, round, blue cell tumor involving bone and soft tissue. The prevalence of EES is only 15%-25% of all Ewing sarcoma and EES often occurs in patients aged from 20-mo-old to 30-years-old resulting in an unfavorable prognosis. CASE SUMMARY: The present case report described a 7-year-old patient with a palpable EES mass of 33 mm × 27 mm × 28 mm in the deep neck with symptoms of persistent dyspnea over the past 5 mo. After laboratory examinations, abnormal physiological and biochemical indicators were not found. Ultrasound images presented the mass to be complex, solid and fluid-filled with circumscribed margins and posterior acoustic enhancement. The mass also presented with partial internal vascularity. The contrast-enhanced magnetic resonance imaging scan illustrated the outstanding enhancement with fast perfusion mode in the early arterial phase. CONCLUSION: Our study suggested that a quick-growing mass in the pediatric patient is possibly a malignant tumor whether the mass has well-defined margins or not.