Initial Management of Lymphoma Brain Metastases with Encephalitis

Immediate Medical Management

• The National Comprehensive Cancer Network recommends starting dexamethasone at 16 mg/day in divided doses for patients with moderate to severe symptoms related to mass effect and cerebral edema 1, 3
• For patients with more acute neurologic issues, higher doses approaching 100 mg/day in divided doses can be considered, as recommended by the National Comprehensive Cancer Network 1
• The National Comprehensive Cancer Network suggests tapering steroids slowly as the clinical situation allows to minimize long-term toxicity, such as personality changes, suppressed immunity, metabolic derangements, insomnia, and impaired wound healing 1, 4

Diagnostic Workup

• The National Comprehensive Cancer Network recommends performing contrast-enhanced MRI of the brain as the gold standard to determine number, size, and location of metastatic lesions 1, 3
• The Journal of Neurology, Neurosurgery and Psychiatry suggests considering brain FDG-PET when there is a high clinical suspicion of encephalitis and other paraclinical studies are uninformative 2
• The Journal of Neurology, Neurosurgery and Psychiatry recommends performing lumbar puncture to support inflammatory etiology and rule out infectious/neoplastic causes, and testing for oligoclonal bands, IgG index, IgG synthesis rate, and neuronal autoantibodies in the CSF 2

Treatment Algorithm Based on Diagnostic Findings

• The Journal of Neurology, Neurosurgery and Psychiatry suggests considering plasma exchange (5-10 sessions every other day) if there is no clinical improvement with standard therapy for infectious encephalitis 2
• The Journal of Neurology, Neurosurgery and Psychiatry recommends considering intravenous immunoglobulin (IVIG) or plasma exchange (PLEX) if there is no clinical improvement with corticosteroids for autoimmune encephalitis 2
• The Annals of Oncology suggests using high-dose methotrexate (HD-MTX) at doses of at least 3 g/m² as the key component of treatment for primary CNS lymphoma or CNS involvement of systemic lymphoma 6

Special Considerations and Pitfalls

• The Journal of Neurology, Neurosurgery and Psychiatry warns that steroid use may mask inflammatory markers in CSF and potentially delay diagnosis of infectious encephalitis 2
• The National Comprehensive Cancer Network recommends avoiding enzyme-inducing anticonvulsants as they can affect metabolism of chemotherapeutic agents 5
• The National Comprehensive Cancer Network suggests monitoring for steroid-related complications, particularly in patients requiring prolonged therapy 1, 4

Follow-up Recommendations

• The National Comprehensive Cancer Network recommends performing serial MRI to assess treatment response 3, 4
• The National Comprehensive Cancer Network suggests tapering steroids as quickly as the clinical situation allows to minimize side effects 1, 3
• The Praxis Medical Insights: Practical Summaries of Clinical Guidelines notes that up to 90% of patients with brain metastases may experience neurocognitive effects 4