A peripheral primitive neuroectodermal tumor arising from the middle turbinate and transnasal endoscopic approach for its surgical treatment

T2-weightened coronal magnetic resonance imaging of maxillofacial region. 25mm×22mm mass lesion limited in the right nasal cavity giving hyperintense signal.

Coronal computerized tomography scans of the paranasal sinuses show the orbit medial wall is intact and the tumor is limited in the right nasal cavity.

Endoscopic view of the right nasal cavity. The polypoid mass is damaging the middle turbinate, and pushing it medially (S: septum; MT: middle turbinate; IT: inferior turbinate; tm: tumor).

On the endoscopic operation, after the debulking of the tumor, the origin of the mass was found as the insertion point of the middle turbinate to the skull base (S: septum; tm: tumor; *the insertion point).

Small and round tumor cells with oval large nucleus and large eosinophilic cytoplasm forming cordons and groups (H&E 400×).

Diffuse cytoplasmic positive immunostaining with NSE (immunohistochemistry NSE 400×).

Focal membranous positive immunostaining with EMA (immunohistochemistry EMA 400×).