Possible neuro-Sweet disease mimicking brain tumor in the medulla oblongata--case report.

A 62-year-old male presented with a rare case of possible neuro-Sweet Disease (NSD) mimicking brain tumor in the medulla oblongata, manifesting as numbness in the bilateral upper and lower extremities, gait disturbance, dysarthria, and swallowing disturbance which gradually deteriorated over 3 months. Magnetic resonance imaging showed a mass lesion in the medulla oblongata, extending to the upper cervical cord with rim enhancement by gadolinium. The preoperative diagnosis was brain tumor, such as glioma, or inflammatory disease. His neurological symptoms gradually deteriorated, so biopsy was performed through the midline suboccipital approach. Histological examination showed infiltration of inflammatory cells, mainly lymphocytes and macrophages. Human leukocyte antigen typing showed Cw1 and B54 which strongly suggested possible NSD. Steroid pulse therapy was started after surgery and the clinical symptoms improved. Neurosurgeons should be aware of inflammatory disorders such as NSD mimicking brain tumor.