The aim of this study is to identify demographic & disease characteristics in pediatric oncology patients diagnosed with Ewing Sarcoma Family of Tumors (ESFT) & treatment outcomes in these patients.

Ewing sarcoma (ES) and peripheral primitive neuroectodermal tumor (PNET), Both entities that currently comprise the same spectrum of neoplastic diseases known as the Ewing sarcoma family of tumors (EFT), were originally described as distinct clinicopathologic entities. Primitive neuroectodermal tumors (PNETs) first described in 1918 by Stout as a malignant tumor arising from major nerve. Later, in 1921, ES was described as an undifferentiated tumor involving the diaphysis of long bones. It was also reported to arise in soft tissue (extraosseous ES). EFT is aggressive malignant small round cell tumors of bone and soft-tissue that predominantly affecting children and young adults.

Inclusion Criteria:

• Patients whose age less than 19 years. Patients diagnosed with Ewing Sarcoma Family of Tumors (ESFT).

Exclusion Criteria:

• Patients whose age more than 19 years. Patients diagnosed with other bone & soft tissue neoplasms.

Pediatric cancer patients, those diagnosed with Ewing Sarcoma Family of Tumors (ESFT), in the period from 2000 January till 2015 December, and received treatment at the pediatric oncology department, their medical records will be retrospectively reviewed for data collection.