[A case of a multiple sclerosis with severe perifocal edema].

We present a case of tumoral multiple sclerosis in a 66-year-old male and emphasize two clinical features: (1) Multiple well-demarcated massive enhanced lesions except for the central area, which was accompanied with severe perifocal edema, occurred within the cerebral hemispheres and should be strongly considered in the diagnosis of mass lesions. The patient underwent partial removal of the mass lesion. The initial histopathological diagnosis of the surgical specimen was astrocytoma grade II. (2) Multiple lesions disappeared completely for one and half months after starting medication using steroid. The reexamination of the surgical specimen was compatible with that of multiple sclerosis. Again, half a month after remission, multiple enhanced lesions without perifocal edema developed in the cerebral and cerebellar hemisphere. The difficulty of the initial diagnosis of multiple sclerosis with severe perifocal edema was discussed, based on our experience.