Malignant ectomesenchymoma of the paranasal sinuses with proptosis.

Abstract A 36-year-old woman presented with a feeling of pressure in the right orbit and proptosis of the right eye after a "common cold". Computed tomography (CT) of the maxillofacial region revealed, and endoscopy confirmed, a mass in the right ethmoid sinus, eroding the lamina papyracea and extending into the orbit. Pathology of multiple biopsies revealed a nasal neoplasm composed of neuroectodermal and mesenchymal neoplastic elements, suggestive of a malignant ectomesenchymoma (MEM). Magnetic resonance imaging was used for MEM staging. Computed tomography of the chest and abdomen show no evidence of distant metastases. Due to the intracranial and intraorbital extension of the tumour, radical surgery was not an option. Appropriate chemotherapy (6 cycles of vincristine/ifosfamide/adriamycin and 2 cycles of vincristine/ifosfamide/cisplatin) and intensity-modulated radiation therapy were administered. Twenty-eight months after treatment, there was no evidence of residual or metastatic disease.