Orbital apex syndrome secondary to sinonasal diffuse large B cell lymphoma: how rare is it?

Abstract

A sinonasal lymphoma is an uncommon form of non-Hodgkin lymphoma (NHL), comprising only 1.5% of all lymphomas. We report a rare case of primary sinonasal diffuse large B cell lymphoma (DLBCL) found accompanying orbital apex syndrome. A 75-year-old Chinese man presented with progressively reduced visual
acuity in the left eye for over 2 months and frequent rhinorrhoea for the previous 4 months. Upon examination, his left eye was noted with poor vision with incomplete ptosis, periorbital fullness, and ophthalmoplegia. Computed tomography scan of the brain and orbit showed nasal soft tissue mass with local extension to the left extraconal space. Histopathological examination of the nasal biopsy tissue showed high-grade DLBCL. The distal cranial neuropathy caused by the lymphomatous infiltration of the left paranasal sinuses had preceded the systemic manifestation. The patient was initiated on chemotherapy and has been, at the time of writing, in remission for 8 months after presentation.