[Primary and metastatic Ewing sarcoma of the skull base - case reports and comparative analysis]

The aim of the present study was to evaluate and compare diagnostic/and treatment modalities of primary and metastatic Ewing sarcoma (ES) of the skull base.

We analyzed nine cases of the skull base ES patients operated in Burdenko Neurosurgical Institute from 2003 to 2011. Among them there were five cases of primary ES, the other four were of metastatic origin. Clinical history, neuroimaging and pathology data together with IHC are presented. Treatment options and results are discussed. Seven patients were operated transcranially, in the other two cases endoscopic endonsnasal operations/were performed. Mean follow up was 11-92 months.

We did not reveal arW pathological or IHC differences between primary and metastatic tumors. The labeling index Ki-67 was insignificantly higher in the metastatic tumors gro'Vip. In one case the patient developed relapse of the metastatic tumour in the temporal bone; he underwent second surgery and died 7 months after the operation.

Despite both metastatic and primary ES of the skull base are of maMignant behavior, the long-term relatively good prognosis can be achieved when combined treatment, including surgery, chemotherapy and radiation is applied.