CONTEXT: Brain metastases are common complications of cancer. Magnetic resonance imaging (MRI), the main diagnostic imaging method in these cases, rarely shows cystic images. CASE REPORT: The patient was a 45-year-old woman who had had severe headache for a month that was refractory to medication, and had previously had breast cancer, which had been treated. The MRI showed the criteria for neurocysticercosis. Since there was no improvement with clinical treatment, we chose to excise the lesions. Histopathological analysis showed an epithelioid malignant neoplasm. CONCLUSION: From immunohistochemical analysis, it was concluded that this was a metastasis of breast carcinoma. Even when the MRI is not characteristic of cerebral metastasis, this hypothesis needs to be ruled out in patients with a previous history of cancer.resUMo CONTEXTO: Metástases cerebrais são complicações comuns do câncer. A ressonância nuclear magnética (RNM), principal método de diagnóstico por imagem nesses casos, mostra raramente imagens císticas. RELATO DO CASO: A paciente era uma mulher de 45 anos de idade, com cefaleia intensa há um mês, refratária à medicação, e câncer de mama tratado previamente. A RNM apresentava critérios diagnósticos para neurocisticercose. Como não apresentou melhora com tratamento clínico, optou-se pela exérese das lesões. O histopatológico mostrou neoplasia maligna epitelioide. CONCLUSÃO: A imunoistoquímica revelou metástase de carcinoma da mama. Mesmo quando a RNM não é característica de metástase cerebral, esta hipótese precisa ser afastada em pacientes com história prévia de câncer.