Neuromyelitis Optica Spectrum Disorders Mimicking Multiple Brain Tumors.

We report a rare case of neuromyelitis optica spectrum disorders (NMOSD), mimicking multiple brain tumors. A 53-year-old woman presented with weakness and paresthesia in her right arm and leg. Upon admission, brain MRI showed about 10 multiple brain tumors, which had to be differentiated from multiple brain metastases, lymphoma, and high-grade glioma in both hemispheres. No primary cancer was found in the chest-abdomen-pelvis CT. Subsequent spine MRI revealed multifocal cord signal change involving C2-T7, suggesting myelitis. A decrease in visual acuity was noted when taking a medical history, and optic neuritis was diagnosed upon ophthalmologic examination. With clinical and radiological appearances, multiple brain and spinal cord lesions have been diagnosed as NMOSD. Steroid and immunosuppressive drugs were administered. We should consider the possibility of an autoimmune disease, such as NMOSD, involving the optic nerve, spinal cord, and central nervous system when multiple hemispheric tumefactive lesions are observed.