PurposeThe purpose of this study is to discuss the clinical presentation, management, and outcomes of patients with primary orbital Ewing sarcoma family of tumors (ESFTs).Patients and methodsRetrospective study of 12 patients with biopsy-proven primary orbital ESFT.ResultsThe mean age at presentation of primary orbital ESFT was 12 years (median, 8 years; range, 5 months to 28 years). There were seven (58%) females and five (42%) males. The presenting complaints included proptosis (n=10; 83%) and swelling in the upper eyelid (n=2; 17%). The mean duration of symptoms was 9 weeks (median, 5 weeks; range, 2-24 weeks). Tumor epicenter was located in the superior orbit (n=6; 50%), lateral orbit (n=3; 25%), inferior orbit (n=2; 17%), and medial orbit (n=1; 8%). Computed tomography of the orbits revealed predominant bony lesion (n=10; 83%) or isolated soft tissue/extraosseous lesion (n=2, 17%). At presentation, extraorbital extension was noticed in 10 patients including intra cranial extension (n=7; 58%), extension into temporal fossa (n=4; 33%), nasal cavity (n=2; 17%), maxillary sinus (n=2; 17%), and ethmoid sinus (n=1, 8%). Systemic metastases at presentation was detected in five (42%) patients involving the bone marrow (n=4; 33%), kidney (n=1; 8%), and retroperitoneal lymphnode (n=1; 8%). Multi-modal treatment including a combination of neoadjuvant chemotherapy, excision biopsy/debulking, and/or radiotherapy was given. Over a mean follow-up period of 21 months (median, 7 months; range, 1-152 months), disease-related death occurred in 11 (92%) cases.ConclusionPrimary orbital ESFT is aggressive at presentation and is associated with poor prognosis.