Tumefactive demyelinating disorders as stroke mimics: Description of cases and systematic review of the literature

Background: tumefactive multiple sclerosis (TmMS) is a rare subtype of a demyelinating disease that develops over time. Cases of hyperacute presentations mimicking cerebrovascular disorders have been reported; however, detailed clinical and demographic data are lacking. Methods: this study aimed to systematically review the literature on tumefactive demyelinating disorders presenting as strokes. After screening the PubMed, PubMed Central, and Web of Science databases, 39 articles describing 41 patients were identified, including 2 historical patients from our center. Results: 23 (53.4%) patients were diagnosed with multiple sclerosis variants (vMS), 17 (39.5%) with inflammatory demyelinating variants (vInf), and 3 with tumors; however, only 43.5% of cases were verified histologically. In subgroup analysis, vMS differed from vInf in several aspects. Inflammatory cerebral spinal fluid parameters, including pleocytosis, proteinorachia was more commonly observed in vInf [11 (64.7%) vs. 1 (5.2%), P = 0.001 and 13/17 (76.4%) vs. 6/23 (31.5%), P = 0.02] than that in vMS. Neurological deterioration and fatal outcomes were more commonly observed in vInf [13/17 (76.4%) vs. 7/23 (30.4%), P = 0.003, and 11/ 17 (64.7%) vs. 0/23 (0%), P = 0.0001] than that in vMS. Conclusions: Clinicodemographic data might aid in recognizing different subtypes of TmMS and warrant consideration of unconventional therapies because outcomes may be poor in the vInf of TmMS.