Metastases

Intramedullary spinal cord metastases (ISCMs) are a rare yet devastating entity in patients with systemic malignancy. Among the largest ISCMs series, the most common origin of the primary tumor is by far lung cancer, followed by breast cancer. If untreated, the natural history of ISCMs consists of rapid buildup of local pressure, cord swelling, ischemia, and potential occurrence of ISCMs at other sites, all of which can precipitate permanent neurologic injury. The role of surgical resection of ISCMs is still unclear, owing to the scarcity of studies on this topic as well as the neurosurgeon's hesitancy to pursue a procedure with a relatively high risk-to-benefit ratio. Assessing the overall disease burden and performance status of the patient will help in the decision-making process. Objective scoring systems, such as the Karnofsky Performance Scale (KPS), Recursive Partitioning Analysis Index (RPAI), and Modified McCormick Score (MMCS), are currently utilized and proven to be successful prognosticators. Patients who will benefit the most from surgical resection of their ISCMs are those with (1) good preoperative overall performance status, (2) solitary ISCMs, (3) fast-growing lesions with rapid neurological decline, (4) lesions with favorable histological types, and/or (5) lesions not responding to radiation therapy. Transient postoperative neurological deterioration may occur, but gradual recovery is expected.