Spinal cord tumors may develop within the spinal cord parenchyma, directly destroying tissue, or outside the cord parenchyma, often compressing the cord or nerve roots. Symptoms can include progressive back pain and neurologic deficits referable to the spinal cord or spinal nerve roots. Diagnosis is by MRI. Treatment may include corticosteroids, surgical excision, and radiation therapy.
Spinal cord tumors may be intramedullary (within the cord parenchyma) or extramedullary (outside the parenchyma).
The most common intramedullary tumors are gliomas, particularly ependymomas and low-grade astrocytomas. Intramedullary tumors infiltrate the spinal cord parenchyma, expand, and destroy the parenchyma. They may extend over multiple spinal cord segments and obstruct the flow of cerebrospinal fluid within the cord, resulting in a syrinx.
Extramedullary tumors may be
Most intradural tumors are benign and are usually meningiomas or neurofibromas, which are the two most common primary spinal tumors.
Most extradural tumors are metastatic. They usually originate as carcinomas of the lungs, breasts, prostate, kidneys, or thyroid or as lymphomas, most commonly non-Hodgkin lymphoma but also Hodgkin lymphoma, lymphosarcoma, and reticulum cell sarcoma.
Both intradural and extradural tumors exert their effects by compressing the spinal cord and its roots, rather than by invading the parenchymal. Most extradural tumors invade and destroy bone before compressing the cord.
Symptoms and Signs
Pain is an early symptom, especially for extradural tumors. It is progressive, unrelated to activity, and worsened by recumbency. Pain may occur in the back, radiate along the sensory distribution of a particular dermatome (radicular pain), or both.
Neurologic deficits referable to the affected level of the spinal cord eventually develop. Common examples are spastic weakness, incontinence, and dysfunction of some or all of the sensory tracts at a particular level of the spinal cord and below. Deficits are usually bilateral.
Intradural extramedullary tumors may be painful when the nerve roots are compressed but can also develop painlessly if the spinal cord is directly compressed without involving the root.
Some patients with intradural tumors—most often meningiomas and neurofibromas—present with sensory deficits of the distal lower extremities, segmental neurologic deficits, symptoms of spinal cord compression, or some combination.
Symptoms of spinal cord compression can worsen rapidly and result in paraplegia and loss of bowel and bladder control.
Symptoms of nerve root compression are also common; they include pain and paresthesias followed by sensory loss, muscular weakness, and, if compression is chronic, muscle wasting, which occurs along the distribution of the affected roots.
Patients with segmental neurologic deficits or suspected spinal cord compression require emergency diagnosis and treatment.
The following suggest spinal tumors:
Diagnosis of spinal cord tumors is by MRI of the affected area of the spinal cord. CT with myelography is an alternative; it can help localize the tumor but provides less information than MRI.
Other spinal masses (eg, abscesses, arteriovenous malformations) and paravertebral tumors can manifest similarly to spinal tumors, but they can typically be distinguished on MRI scans.
Spinal x-rays, taken for other reasons, may show bone destruction, widening of the vertebral pedicles, or distortion of paraspinal tissues, especially if the tumor is metastatic.
If patients have neurologic deficits due to spinal cord compression, corticosteroids (eg, dexamethasone 100 mg IV, then 10 mg po qid) are begun immediately to reduce spinal cord edema and preserve function. Tumors compressing the spinal cord are treated as soon as possible because deficits may quickly become irreversible.
Some well-localized primary spinal cord tumors can be excised surgically. Deficits resolve in about half of these patients. If tumors cannot be surgically excised, radiation therapy is used, with or without surgical decompression. Compressive metastatic extradural tumors are usually surgically excised from the vertebral body, then treated with radiation therapy. Noncompressive metastatic extradural tumors may be treated with radiation therapy alone but may require excision if radiation therapy is ineffective.