Sinonasal Lymphoma Presenting as Cavernous Sinus Syndrome: Case Report and Review of the Literature.

A 37-year-old man presented with a 1-week history of diplopia. He was under investigation by otorhinolaryngology for left sinonasal malignancy after imaging of the paranasal sinuses had revealed a large homogenous mass in the left nasal cavity. His visual acuity was 6/9 in each eye with no relative afferent pupillary defect. The left pupil, though was mid-dilated and unresponsive to light. He had a left-sided ptosis. Extraocular movements of the left eye were restricted in all directions of gaze and there was with limited abduction, dextroelevation and dextrodepression of the right eye. A trans-nasal biopsy revealed extranodal natural killer/T-cell lymphoma. Further imaging showed a large enhancing nasopharyngeal mass with intracranial extension to the cavernous sinuses and local infiltration together with intracranial abscesses. The patient was started on empirical intravenous antibiotics and supportive treatment. While awaiting institution of lymphoma chemotherapy, he died. The involvement of the cavernous sinus in sinonasal lymphoma represents an advanced stage. This case highlights that lymphoma should be considered in any patient presenting with a cavernous sinus syndrome and sinonasal disease.