LAUSR

Primary central nervous system lymphoma (PCNSL) is a variant of non-Hodgkin lymphoma, affecting the brain, leptomeninges, eyes, and spinal cord. PCNSL is a progressive disease with symptom onset occurring over weeks that presents with varied signs and symptoms, including focal neurological deficits, mental status changes, behavioral changes and seizures. Tissue diagnosis is imperative, though MRI, ophthalmologic and CSF evaluation can aid in diagnosis. PET scan and bone marrow biopsy are important for assessing metastatic spread following diagnosis. We present a case series, comprised of three patients with atypical presentations of CNS lymphoma. Patient 1. 64 year old male presented with facial muscle weakness, vertigo, and diplopia. Initial MRI showed an old thalamic and new internal capsule infarcts. EMG suggested sensorimotor peripheral neuropathy consistent with Guillain-Barre Syndrome, leading to treatment with a five day course of IVIG. His MRI findings gradually worsened, ultimately revealing leptomeningeal enhancement of the bilateral vestibulococchlear nerves, facial nerves and the trigeminal nerves. Patient 2. 66 year old male with a past medical history of primary cutaneous anaplastic T cell lymphoma stage 1 EA, status post field radiation, presented with aphasia and ataxia. Brain MRI showed extensive, enhancing hyperdensities in the midbrain, suggestive of multiple sclerosis, prompting treatment with steroids. He continued to clinically worsen, prompting tissue diagnosis. Patient 3. 66 year old male presented with recurrent syncopal episodes and aphasia, found to have a 4 cm extra axial mass in the left temporal region on MRI suggestive of a meningioma. All three patients eventually underwent brain biopsy with a final histologic diagnosis of PCNSL. Due to the highly variable initial presentation of this condition and the wide range of pathologies it mimics, CNS lymphoma should be included in the differential diagnosis of patients presenting with atypical neuroimaging or clinical findings.