RESUMO
Intramedullary metastases are rare, accounting for 0.9-5% of spinal metastases. Radiation myelopathy is considered one of the most distressing complications of radiotherapy. In both cases symptoms are aspecific, and there are no characteristic neuroradiologic findings. We describe a case of single intramedullary metastasis from lung microcytoma in a 55-year-old man with a history of malignancy, treated by radiotherapy five years previously. The patient returned to our observation complaining of pain and paraesthesia in the left C7 area. Spinal MRI and rachicentesis findings were aspecific. Ten days later a new MRI showed that the lesion size had increased, and neoplastic cells were found in CSF. Intramedullary metastases are extremely rare, accounting for 0.1-0.4% of all CNS tumors. The risk of developing delayed radionecrosis varies with the total dose administered. In both cases diagnosis is histological, while contrast-enhanced MRI is highly sensitive and specific in identifying and characterizing the lesion. In case of metastatic lesions the prognosis is unfavorable. Differential diagnosis is important because it has a strong effect on patient management.