Ewing's Sarcoma Family Tumors in the Jaws: Case Report, Immunohistochemical Analysis and Literature Review

Abstract

Due to the low incidence of the Ewing's Sarcoma (ES) family tumors, the available epidemiology is likely to be unreliable, and at present, there are no standard diagnostic or clinical guidelines outlining their management. This report describes a case of peripheral primitive neuroectodermal tumor (ES/pPNET) which initially mimicked cystic lesions, and describes a comparison between ES and ES/pPNET in the jaws by the World Health Organization classification. This review addressed 63 cases published in the English literature between 1950 and 2016. The majority of cases were ES. Both ES and ES/pPNET mimicked other benign entities such as traumatic, cystic and inflammatory lesions. The patients who died of their disease had a history of metastatic tumors, and primary tumor located in the mandible and maxilla for ES and ES/pPNET, respectively. The differentiation of the ES family tumors from other small blue-cell tumors may be difficult and requires familiarity with histological and immunohistochemical features.

Keywords: Ewing's sarcoma; histological features; peripheral primitive neuroectodermal tumor.

Figure 1. Cone beam computed tomography of Ewing’s sarcoma/peripheral primitive neuroectodermal tumor showing enlargement of hypodense osteolytic area (A and B) and coronal section showing lingual cortical bone resorption close to the first molar (C)

Figure 2. Histopathological features of Ewing’s sarcoma/peripheral primitive neuroectodermal tumor (ES/pPNET). A: ES/pPNET exhibiting fibrous connective tissue capsule infiltrated by highly cellular tumor (hematoxylin and eosin, ×4). B: Tumor island and strand of small round blue cells with well-defined hyperchromatic nuclei and scant cytoplasm (hematoxylin and eosin, ×40).

Figure 3. Periodic acid-Schiff (PAS) and immunostaining in Ewing’s sarcoma/peripheral primitive neuroectodermal tumor (ES/pPNET). A: PAS stain with diastase pretreatment (×40). Diffuse and strong positivity for CD99 (B), vimentin (C), S-100 protein (D) and neuron-specific enolase (E) (×10).