Mass lesions in the brain: tumor or multiple sclerosis? Clinical and imaging characteristics and course from a single reference center

Turk Neurosurg. 2013;23(6):728-35. doi: 10.5137/1019-5149.JTN.7690-12.3.


Aim: 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.

Material and 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).

Conclusion: 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.

MeSH terms

  • Adolescent
  • Adult
  • Age of Onset
  • Biomarkers, Tumor / cerebrospinal fluid
  • Biopsy
  • Brain Edema / diagnosis
  • Brain Edema / etiology
  • Brain Neoplasms / cerebrospinal fluid
  • Brain Neoplasms / diagnosis*
  • Brain Neoplasms / pathology
  • Demyelinating Diseases / diagnosis
  • Demyelinating Diseases / pathology
  • Diagnosis, Differential
  • Disease Progression
  • Female
  • Follow-Up Studies
  • Humans
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Imaging
  • Magnetic Resonance Spectroscopy
  • Male
  • Middle Aged
  • Multiple Sclerosis / cerebrospinal fluid
  • Multiple Sclerosis / diagnosis*
  • Multiple Sclerosis / pathology
  • Nervous System Diseases / diagnosis
  • Nervous System Diseases / etiology
  • Retrospective Studies
  • Spinal Cord Diseases / diagnosis
  • Spinal Cord Diseases / etiology
  • Young Adult


  • Biomarkers, Tumor