Recurrent Mandibular Ewing Sarcoma in an 11-Year-Old Boy: A Rare Pediatric Case and Review of the Literature Publisher Pubmed



Nourbakhsh S M K ; Shirkhoda M ; Jangjoo T
Source: Journal of Medical Case Reports Published:2026

Abstract

Rationale: Mandibular Ewing sarcoma is exceptionally rare in children and frequently mimics common odontogenic infections. This overlap leads to delayed diagnosis and potentially rapid tumor progression. Early recognition and appropriate multimodal management are critical for improving outcomes. Patient concerns: An 11.5-year-old Iranian boy of Middle Eastern ethnicity presented with progressive left mandibular swelling and pain for 1 month, unresponsive to antibiotic therapy previously prescribed for presumed dental abscess. Diagnosis: Imaging (CT, MRI) revealed an aggressive destructive mandibular lesion with periosteal reaction. Histopathology showed small round blue cells, and immunohistochemistry demonstrated CD99 and NKX2.2 positivity, confirming Ewing sarcoma. Staging PET–CT showed mandibular involvement without distant metastatic disease. Interventions: The patient received neoadjuvant chemotherapy according to the Euro-EWING99 protocol using alternating vincristine, doxorubicin, and cyclophosphamide (VDC) and ifosfamide/etoposide (IE). Following local recurrence, salvage treatment with nivolumab, temozolomide, and irinotecan was administered, followed by ICE chemotherapy, radiotherapy, and ultimately left hemimandibulectomy with fibular free-flap reconstruction. Outcomes: Despite multiple local recurrences during treatment, the patient ultimately underwent left hemimandibulectomy with fibular free-flap reconstruction. Postoperative PET–CT demonstrated complete metabolic remission, and the patient remained disease-free at the most recent 6-month follow-up. Lessons: This case highlights the importance of early biopsy for atypical mandibular swellings in children and the role of multimodal treatment—including immunotherapy—as a promising option in relapsed Ewing sarcoma. Persistent jaw masses in pediatric patients should raise concern for malignancy, even when clinical presentation mimics infection. © The Author(s) 2026.