Clinical features and natural history of intramedullary spinal cord metastasis.

Five cases of intramedullary spinal cord metastasis are presented and an additional 50 cases from the English language literature since 1960 are reviewed. Lung cancer and breast cancer were the most frequently occurring primary neoplasms, but a wide variety of solid tumors may cause intramedullary spinal cord metastasis. The presenting symptoms were pain and/or weakness. The neurologic status deteriorated rapidly in the majority of patients in a period to days to weeks. Progression to a cord hemisection syndrome or cord transection occurred in approximately half of the patients. The characteristic myelographic appearance of fusiform swelling of the cord was seen in one third of the patients, but the myelogram was normal in 42%. Plain radiographs of the spine showed no evidence of metastatic disease in three fourths of cases. The cerebrospinal fluid protein level was frequently elevated, but results of cytologic studies were usually negative. High-resolution computer-assisted tomographic scanning may show intramedullary metastases. Radiation therapy combined with corticosteroid administration offers the only effective palliation. The recognition of intramedullary spinal cord metastasis is an ominous finding. Intramedullary spinal cord metastasis generally occurred in the setting of widespread systemic and intracranial disease, but occasionally was the only site of relapse. More than 80% of patients died within 3 months. Heightened awareness of this entity may lead to early diagnosis at a stage when neurologic deficits are reversible and, it is hoped, more effective palliation can be achieved.