Table 4.

Neurologic complications of cancer

Complication	Metastases/Disorders	Description	Clinical Presentation	Diagnosis	Treatment
Direct	Brain metastases[65,66]	The most frequent direct form of involvement of the nervous system by cancer	Focal neurologic deficits, headaches, seizures	MRI and CT scan devices	Symptomatic therapy for seizures and vasogenic edema Anticonvulsants Dexamethasone Surgery and radiation therapy
	Leptomeningeal metastases[67,68]	It is when cancer spreads to the membranes lining the spinal cord and the brain. Mostly seen in breast cancer, melanoma, and acute nonlymphocytic leukemia	Involvement of the nerve root and spinal cord Multiple cranial neuropathies Patients with weakness of limb, Pain in the involved nerve roots or bladder Bowel disturbances	Could be detected through sensory loss, weakness, and changes in deep tendon reflexes. Presence of malignant cells in the cerebrospinal fluid is a sign Techniques of polymerase chain reaction and flow cytometry	Chemotherapy Radiation Surgery Cytarabine Direct spinal fluid injection of rituximab, topotecan, etoposide, thiotepa, cytarabine, and methotrexate
	Spine metastases[69,70]	These types of metastases are prevalent in cancer patients Epidural spinal cord compression resulted mainly from the breast, lung, and prostate cancer It represents >95% of the spine metastases cases	Pain Involvement of the thoracic spine Mid-back pain Lower extremity bilateral weakness	Neuroimaging CT Myelography	High-dose steroid therapy (dexamethasone) Pain therapy with corticosteroids Radiation therapy Kyphoplasty or vertebroplasty for pain relief
	Peripheral nervous system metastases[71]	Cancer involves the nervous system directly. Metastases to the nerve roots and plexi are more common than individual nerves	Sensorimotor deficits and pain in one limb Involvement of the lower and upper plexus Injury to the entire plexus from the infiltrating neoplasm Adduction and eversion Weakness of thigh flexion Involvement of the brachial or cervical plexus Numbness or weakness Orofacial numbness	Neuroimaging with MRI Nerve conduction studies Studies with electromyography	Analgesics and steroids (pain killers) Tricyclic or other antidepressants Anticonvulsants Gabapentin and pregabalin Chemotherapy and radiation
Indirect	Paraneoplastic Syndromes[72]	These syndromes are without direct infiltration Without metastases Without compression PNS or CNS structure	Insomnia, Seizures, Memory loss, Weakness, Fatigue, Autonomic dysfunction, Neuropathy	It is an autoimmune disease and provides the possibility of early cancer diagnosis	Corticosteroids Benzodiazepines Plasmapheresis IVIg Steroids Chemotherapy
	Lambert-Eaton myasthenic syndrome[73]	It is a kind of neuromuscular syndrome	Fatigue Autonomic dysfunction Fluctuating weakness	Electromyography (EMG)/NCS	3,4-Diaminopyridine Immunomodulatory therapy (with plasmapheresis and IgG) Long-term steroid therapy