Sinonasal poorly differentiated carcinoma presenting clinically as esthesioneuroblastoma

Abstract

5605 Background: Sinonasal undifferentiated carcinoma presenting clinically as esthesioneuroblastoma is a rare finding. Method: A 54 year old white male presented with progressive double vision, left nasal congestion, proptosis of left eye and intermittent pain in left eye and frontal sinus region of 7–8 months duration. Examination revealed a large deforming mass involving the left proximal nasal cavity extending into the mid forehead protruding through the frontal bone. Intranasal cavity revealed edematous mucosa with soft tissue mass filling mid aspect of nasal cavity on the left. Neurological examination was non focal. CT scan revealed a large destructive mass involving the left nasal cavity and ethmoid sinus extending into the left orbit with displacement of the globe and destruction of the anterior cranial fossa including the frontal bone. MRI revealed a large sinonasal tumor (5.2x7x7.5cm) extending through the cribriform plate, anteromedial floor of the middle cranial fossa and through the inner and outer table of the frontal bones, more to the left than to the right of midline. A mass effect on the brain was noted but primarily appeared to be displacing rather than invading the brain. Result: Biopsy revealed poorly differentiated carcinoma. IHC stains showed cytokeratin positivity and were negative for CD99, NSE and synaptophysin. He is currently being treated with combined radiation therapy and chemotherapy (carboplatin/paclitaxel). Conclusion: Here we describe a patient who initially presented with signs and symptoms clinically and radiologically highly suspicious for esthesioneuroblastoma(ONB) but found to have carcinoma as per histology, which is a rare presentation. ONB is a rare tumor located in the roof of the nasal cavity and paranasal sinuses. Immunohistochemically, it typically exhibit positive staining for NSE, synaptophysin and chromogranin. These are negative for a variety of other markers, including CD99. Sinonasal undifferentiated carcinoma(SUC) cells are reactive for cytokeratin (90%) and EMA (65%). SUC behaves aggressively. Most patients have locally extensive disease and often, distant metastases at diagnosis. Multimodality approaches (eg, sequential chemotherapy, radiation therapy and craniofacial resection) can cure some patients with localized disease. No significant financial relationships to disclose.