Defining the course of tumefactive multiple sclerosis: A large retrospective multicentre study

Background and purpose: Tumefactive multiple sclerosis (TuMS) (i.e., MS onset presenting with tumefactive demyelinating lesions [TDLs]) is a diagnostic and therapeutic challenge. We performed a multicentre retrospective study to describe the clinical characteristics and the prognostic factors of TuMS. Methods: One hundred two TuMS patients were included in this retrospective study. Demographic, clinical, magnetic resonance imaging (MRI), laboratory data and treatment choices were collected. Results: TuMS was found to affect women more than men (female:male: 2.4), with a young adulthood onset (median age: 29.5years, range: 11–68 years, interquartile range [IQR]: 38 years). At onset, 52% of TuMS patients presented with the involvement of more than one functional system and 24.5% of them with multiple TDLs. TDLs most frequently presented with an infiltrative MRI pattern (38.7%). Cerebrospinal fluid immunoglobulin G oligoclonal bands were often demonstrated (76.6%). In 25.3% of the cases, more than one acute-phase treatment was administered, and almost one-half of the patients (46.6%) were treated with high-efficacy treatments. After a median follow-up of 2.3years (range: 0.1–10.7 years, IQR: 3.4 years), the median Expanded Disability Status Scale (EDSS) score was 1.5 (range: 0–7, IQR: 2). Independent risk factors for reaching an EDSS score ≥3 were a higher age at onset (odds ratio [OR]: 1.08, 95% confidence interval [CI]: 1.03–1.14, p&nbsp