[Recurrence of peripheral primitive neuroectodermal tumor of the orbit with systemic metastases].

CASE REPORT A six-year-old boy presented with proptosis of the right eye. Imaging studies detected a mass in the medial wall of the right orbit. This mass was biopsied revealing a histopathologic diagnosis of primitive neuroectodermal tumor, so chemotherapy treatment was given. After seven years in remission he presented with a recurrence of the orbital tumor and was found to also have systemic metastases. Treatment with chemotherapy, radiotherapy and orbital exenteration was unsuccessful. DISCUSSION The orbital occurrence of these tumors is extremely rare. Differentiation from other small round cell tumors requires immunohistochemical and ultrastructural techniques.