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Reversible extralimbic paraneoplastic encephalopathies with large abnormalities on magnetic resonance images
Andrew McKeon1, J Eric Ahlskog, Jeffrey W Britton
1Department of Neurology, Mayo Clinic College of Medicine, 200 First St SW, Rochester, MN 55905, USA.
Objective:
To describe reversible extralimbic paraneoplastic encephalopathies with large, lobar lesions on magnetic resonance imaging (MRI).
Design:
Case series.
Setting:
Autoimmune Neurology Clinic, Mayo Clinic, Rochester, Minnesota.
Results:
Three patients had large confluent areas of signal abnormality on T2-weighted MRI, including frontal in 2 and frontal and occipital in 1. Patient 1, a woman aged 63 years, experienced hemiparesis with hemianopia 3 years after a diagnosis of adenocarcinoma of the breast. Nine years later, rapidly progressive dementia developed. Patient 2, a woman aged 79 years, presented with monoparesis and epilepsia partialis continua, 1 year after a diagnosis of adenocarcinoma of the breast. Patient 3, a man aged 65 years, had paraneoplastic sensory neuronopathy, limbic encephalitis, antineuronal nuclear autoantibody type 1 (ANNA-1), and squamous cell carcinoma of the lung. He was stable for 3 years after treatment. Subacute onset of aphasia, delirium, worsening seizures, and rising ANNA-1 titers led to a diagnosis of recurrent limited carcinoma. Brain MRI abnormalities in all patients improved dramatically after immunotherapy. Two patients had sustained clinical remission.
Conclusion:
Recognition of paraneoplastic extralimbic lobar encephalopathies is important because these disorders and their underlying cancers are treatable.
Insights
Paraneoplastic extralimbic encephalopathies, characterized by large brain lesions, are treatable neurological disorders. Early recognition and immunotherapy can lead to significant clinical improvement and remission.
Area of Science:
- Neurology
- Neuroimmunology
- Oncology
Background:
- Paraneoplastic syndromes involve immune responses to cancer that affect the nervous system.
- Extralimbic paraneoplastic encephalopathies are rare and can present with diverse neurological deficits.
Observation:
- Three patients presented with reversible extralimbic paraneoplastic encephalopathies.
- Magnetic resonance imaging (MRI) revealed large, lobar lesions in the frontal and/or occipital lobes.
- Patients had associated cancers, including breast and lung adenocarcinoma.
Findings:
- Neurological symptoms included dementia, hemiparesis, hemianopia, monoparesis, and seizures.
- All patients showed dramatic improvement in brain MRI abnormalities following immunotherapy.
- Two patients achieved sustained clinical remission.
Implications:
- Prompt diagnosis of these encephalopathies is crucial for effective treatment.
- Immunotherapy offers a viable treatment option for both the neurological disorder and the underlying cancer.
- This highlights the importance of considering paraneoplastic syndromes in patients with unexplained neurological symptoms and cancer.
