title: Mass lesions in the brain: tumor or multiple sclerosis? Clinical and imaging characteristics and course from a single reference center.
abstract: OBJECTIVE
  In demyelinating disease spectrum, tumor-like (tumefactive) demyelinating lesions (TDL) are rarely seen. Atypical imaging and clinical features of these lesions may cause misdiagnosis of tumor or abscess.
  
  
  METHODS
  25 patients with TDL in our center were followed and clinical, magnetic resonance imaging (MRI), magnetic resonance spectroscopy, cerebrospinal fluid (CSF) findings and disease course were retrospectively evaluated.
  
  
  RESULTS
  Mean age at symptom onset was 29 years. Motor and sensory deficits were most common symptoms and 18 of them were polysymptomatic. Mostly frontal and parietal regions were affected. 10/25 patients were initially misdiagnosed clinically as brain abscess, primary central nervous system tumor metastasis. T2-hypointense rim, incomplete ring enhancement of the lesions on post-gadolinium T1- weighted imaging on brain MRI enabled accurate diagnosis of TDLs. 13 of 21 patients with first-TDL presentation sustained a monophasic course, remaining 8 patients converted to multiple sclerosis (MS) at a mean 38.4 months follow-up. Clinical isolated syndrome (CIS) patients were older than patients who developed MS and Expanded Disability Status Scale was lower (0.96 vs 3.7).
  
  
  CONCLUSIONS
  Although MRI, CSF and pathologic examination help in differential diagnosis of the mass lesions, close follow-up is still crucial for the definite diagnosis. A higher MS conversion rate was found in patients with a younger TDL onset age.
authors: Hacettepe University, Faculty of Medicine, Department of Neurology, Ankara, Turkey.
authors: Ahmet Kasim
authors: AK
authors: Kilic
authors: Asli Tuncer
authors: AT
authors: Kurne
authors: Kader Karli
authors: KK
authors: Oguz
authors: Figen
authors: F
authors: Soylemezoglu
authors: Rana
authors: R
authors: Karabudak
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D014408:Biomarkers, Tumor / Q000134:cerebrospinal fluid; D001706:Biopsy; D001929:Brain Edema / Q000175:diagnosis / Q000209:etiology; D001932:Brain Neoplasms / Q000134:cerebrospinal fluid / Q000175:diagnosis* / Q000473:pathology; D003711:Demyelinating Diseases / Q000175:diagnosis / Q000473:pathology; D003937:Diagnosis, Differential; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000134:cerebrospinal fluid / Q000175:diagnosis* / Q000473:pathology; D009422:Nervous System Diseases / Q000175:diagnosis / Q000209:etiology; D012189:Retrospective Studies; D013118:Spinal Cord Diseases / Q000175:diagnosis / Q000209:etiology; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor