Masses in the membranes.

A 24-year-old woman with systemic lupus erythematosus presented with a 1-year history of painless vision loss in the right eye. Examination was notable for a bitemporal hemianopia. Brain imaging revealed multiple contrast enhancing dural masses, including one along the planum sphenoidale. She underwent excisional biopsy for a presumed diagnosis of multiple meningiomas. Five years later, she developed worsening vision in the left eye, hypesthesia in the V1 distribution, and oculomotor nerve palsy. Repeat imaging showed an enhancing mass in the cavernous sinus and orbital apex. Biopsy demonstrated a lymphoplasmacyte rich infiltrate in dense extracellular material. She was diagnosed with lupus-induced hypertrophic pachymeningitis and started on immunosuppressive therapy. On further worsening of symptoms, her initial biopsy was reexamined and revealed a kappa light chain restricted B-cell and plasmacyte population. This led to the final diagnosis of central nervous system extranodal marginal zone lymphoma.