A challenging case of concurrent multiple sclerosis and anaplastic astrocytoma

BACKGROUND: Cases of gliomas coexisting with multiple sclerosis (MS) have been described over the past few decades. However, due to the complex clinical and radiological traits inherent to both entities, this concurrent phenomenon remains difficult to diagnose. Much has been debated about whether this coexistence is incidental or mirrors a poorly understood neoplastic phenomenon engaging glial cells in the regions of demyelination. CASE DESCRIPTION: We present the case of a 41-year-old patient diagnosed with a left-sided frontal contrast enhancing lesion initially assessed as a tumefactive MS. Despite systemic treatment, the patient gradually developed signs of mass effect, which led to decompressive surgery. The initial microscopic evaluation demonstrated the presence of MS and oligodendroglioma; the postoperative evolution proved complex due to a series of MS-relapses and tumor recurrence. An ulterior revaluation of the samples for the purpose of this report showed an MS-concurrent anaplastic astrocytoma. We describe all relevant clinical aspects of this case and review the medical literature for possible causal mechanisms. CONCLUSION: Although cases of concurrent glioma and MS remain rare, we present a case illustrating this phenomenon and explore a number of theories behind a potential causal relationship.