RESUMEN
OBJECTIVE: We present a case of relapsing tumefactive demyelination in a young female patient, that posed a real diagnostic challenge, with a heterogeneous clinical picture, atypical for multiple sclerosis (MS) presentation, and neuroradiological manifestations with a high suspicion of neoplastic diseases. CASE REPORT: An 18-year old female patient presented to our Neurosurgical Out-patients' Clinic with symptoms atypical for multiple sclerosis, unremarkable neurological deficit, one tumefactive lesion on MRI, followed by relapse and another two lesions within a period of six months. We decided to perform biopsy of the tumefactive lesion with compressive effect. Serological and clinical data were negative for MS, and the patient did not respond well to corticosteroid therapy. Fresh frozen tumor tissue aroused a strong suspicion of gemistocytic astrocytoma, so total resection was done, but the definitive pathohistological examination confirmed tumefactive demyelination. CONCLUSION: For clinicians, it is important to consider demyelinating disease in the differential diagnosis of a tumorlike lesion of the central nervous system, in order to avoid invasive and potentially harmful diagnostic procedures, especially in younger patients.