IgG4-related disease (IgG4RD) with intracranial involvement is rare. We report a 56-year-old male who had an excellent response to rituximab and dexamethasone after going undiagnosed for 5 years. After 3 years of rituximab maintenance, he has no evidence of disease on brain MRI.

A 26-year-old female developed bilateral blindness after a complete remission for ALK-positive ALCL. Initial workup showed neurolymphomatosis involving the bilateral optic nerves. She underwent hematopoietic cell transplantation and she remained in complete remission after 1 year; however her vision never improved. ALCL likely led to destruction of the optic pathway.