Neurologic complications of systemic cancer.

Neurologic complications of systemic cancer are common. Metastatic complications include intracranial metastasis, spinal metastasis, leptomeningeal metastasis, and metastasis to peripheral nerves. Treatment is often effective in preventing further neurologic disability and pain. Early diagnosis is important. Nonmetastatic complications of systemic cancer include a wide variety of neurologic illnesses that can also occur in the noncancer population. The most common is toxic metabolic encephalopathy. Other nonmetastatic complications include cerebrovascular complications, complications of treatment, immunocompromised infections, and paraneoplastic syndromes.