Abstract
Acute demyelination may present as a rapidly expanding space-occupying or tumefactive lesion (TDL). Tumefactive demyelinating lesions are misdiagnosed quite frequently and can result in unnecessary and potentially harmful surgical resection, radiation or toxic chemotherapeutic interventions therapy. Systematic literature review from available articles and abstracts in PubMed database was summarized in purpose to describe typical presentation and diagnostically challenging features of TDL. One clinical case report presenting tumor-like lesion of the brain, when the diagnosis of TDL was established, is added as an illustrative material.