Malignant ectomesenchymoma of the orbit in a child: Case report and review of the literature.

Malignant ectomesenchymoma is a rare soft tissue tumor of childhood composed of both mesenchymal and neuroectodermal elements. Reported sites of origin are head and neck, abdomen, perineum, scrotum, and extremities. A new case of an orbital ectomesenchymoma in a 7-year-old boy is presented. The clinical picture of the tumor, radiological findings, and its histopathologic and immunohistochemical characteristics are described. The patient was successfully treated with combined surgical resection and chemotherapy. All the other reported cases of malignant ectomesenchymoma with various sites of origin are also reviewed.