Rituximab Monotherapy for Compressive Optic Neuropathy With Giant Ocular Adnexal Mucosa-Associated Lymphoid Tissue lymphoma.

A rare case of compressive optic neuropathy due to giant mucosa-associated lymphoid tissue lymphoma in the orbit was presented. A 87-year-old woman was aware of a slow progressive left ocular proptosis for 10 years and presented after becoming aware of a sudden progression of the proptosis accompanying visual disturbance over the previous 2 months. Orbital imaging and a biopsy of the tumor revealed a mucosa-associated lymphoid tissue lymphoma occupying her left orbit compressing and stretching the left optic nerve. Considering her age and the additional adverse effects of external beam radiation therapy to her damaged optic nerve, rituximab monotherapy was utilized. The intervention resulted in almost complete regression without any serious adverse effect, with left eye best-corrected visual acuity improving from 12/200 to 16/20. Rituximab monotherapy can be one of the first-choice treatment options for mucosa-associated lymphoid tissue lymphoma, especially in cases with the critical damage in the optic nerve.