Tumefactive demyelination: updated perspectives on diagnosis and management

ABSTRACT

Introduction

Tumefactive demyelination (TD) can be a challenging scenario for clinicians due to difficulties distinguishing it from other conditions, such as neoplasm or infection; or with managing the consequences of acute lesions, and then deciding upon the most appropriate longer term treatment strategy.

Areas covered

The authors review the literature regarding TD covering its clinic-radiological features, association with multiple sclerosis (MS), and its differential diagnosis with other neuroinflammatory and non-inflammatory mimicking disorders with an emphasis on atypical forms of demyelination including acute disseminated encephalomyelitis (ADEM), MOG antibody-associated demyelination (MOGAD) and neuromyelitis spectrum disorders (NMOSD). We also review the latest in the acute and long-term treatment of TD.

Expert opinion

It is important that the underlying cause of TD be determined whenever possible to guide the management approach which differs between different demyelinating and other inflammatory conditions. Improved neuroimaging and advances in serum and CSF biomarkers should one day allow early and accurate diagnosis of TD leading to better outcomes for patients.

KEYWORDS:

• Multiple sclerosis
• atypical
• pseudotumour
• differential diagnosis
• MRI
• treatment
• ADEM
• NMOSD
• Balo
• Marburg
• Schilder
• MOGAD
• treatment
• prognosis

Article Highlights

• TD can be challenging to distinguish from primary or secondary brain neoplasms and can occur due to a number of different inflammatory demyelinating conditions, but MS is the commonest eventual diagnosis.

• The term ‘tumefactive MS’ is imprecise and should be avoided in favour of ‘tumefactive demyelination’

• Features highly suggestive of TD over tumour are minimal or absent mass effect for the size of the lesion, and an open-ring pattern of enhancement.

• A glutamate/glutamine peak on MR spectroscopy, a decreased cerebral blood volume on perfusion MRI studies, and little or no uptake on CT-PET can provide supportive information that favours TD over a high-grade brain tumour.

• The presence of unmatched oligoclonal bands (OCBs) in CSF at TD-onset predict a higher probability of conversion to MS, but most patients who present with an isolated TD lesion will have negative OCBs.

• Acute treatment of TD consists of high dose intravenous methylprednisolone and plasma exchange and case reports indicate that rituximab or cyclophosphamide can be used for refractory cases, with decompressive craniectomy reserved for life threatening cases.

• It is critical that clinicians try to make a diagnosis as to the cause of a TD as long-term treatment strategy to prevent relapse depends on the cause of the TD and may include MS disease modifying therapies or other immunosuppression.

• Longer term treatment decisions are most difficult in patients with isolated TD lesions or in those with overlapping seronegative NMOSD/MS phenotypes.

• Close clinical and radiological follow-up of patients with TD is recommended to ensure an appropriate treatment strategy has been adopted and to allow changes to treatment as required.

• MS patients with TD lesions who make a good recovery from their initial attack may have a favourable prognosis compared to classical MS patients, but quality data are lacking.

Declaration of interest

T Hardy has received speaking fees or honoraria for serving on advisory boards for Biogen, Merck, Teva, Novartis, Roche, Bristol Meyers Squibb and Sanofi-Genzyme. He is Co-Editor of Advances in Clinical Neurosciences and Rehabilitation. P Sánchez has received speaking fees from Roche. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or conflict with the subject matter or materials discussed in this manuscript apart from those disclosed.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.