Sinonasal Ewing's Sarcoma/Primitive Neuroectodermal Tumor

Sinonasal Ewing's sarcoma/ primitive neuroectodermal tumor (PNET) with confirmed diagnosis and follow-up data has rarely been reported in literature. Four patients with Ewing's sarcoma/PNET are presented and their managements are discussed. One of our patients had Ewing sarcoma/PNET as a second tumor after treatment of hepatoblastoma, which has never been reported in the literature. They presented with nasal obstruction, nasal bleeding, proptosis, facial or neck mass. Their image studies all demonstrated huge tumors growing from maxillary or ethmoid sinuses with extension to surrounding tissue, and one demonstrated neck lymph node enlargement. Pathological examination of all tumor showed typical small round cell tumor and had strong immunoreactivity to CD99 immunochemistry staining. One patient only received wide excision, while the rest of them received combined treatment with chemotherapy surgery or radiotherapy. One patient died of bone metastasis; one lost to follow-up at 40 months post operation; the other two remain disease free. Sinonasal Ewing sarcoma/PNET is rare and difficult to treat. Multimodality treatment might provide better disease control and lower morbidity.