Differential diagnosis between intracranial dissemination of spinal cord astrocytoma and paraneoplastic limbic encephalitis

We describe the clinical features of limbic encephalitis that developed after palliative spinal cordotomy in 2 patients with malignant thoracic astrocytoma. Both patients showed short-term memory loss, hallucinations of smells and psychiatric symptoms. Brain MRI on T2-weighted and fluid-attenuated inversion recovery sequences revealed high intensity lesions in bilateral temporal lobe areas. We considered that both patients had paraneoplastic limbic encephalitis associated with astrocytoma because of various clinical and radiological features. But the possibility of intracranial dissemination of astrocytoma could not be fully excluded. The differential diagnosis between intracranial dissemination of spinal cord astrocytoma and paraneoplastic limbic encephalitis may be sometimes difficult.