Spinal 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.
(See also Overview of Spinal Cord Disorders.)
Spinal tumors may be intramedullary (within the cord parenchyma) or extramedullary (outside the parenchyma).
Spinal tumors may also be
Primary: Originating in the spine)
Secondary: Originating elsewhere in the body
Intramedullary tumors
The most common intramedullary tumors are gliomas, particularly ependymomas and low-grade astrocytomas. Intramedullary tumors infiltrate the parenchyma and expand rather than displace the spinal cord. Intramedullary tumors may extend over multiple spinal cord segments and obstruct the flow of cerebrospinal fluid within the cord, resulting in a peritumoral syrinx.
Extramedullary tumors
Extramedullary tumors may be
Intradural: Located within the dura but outside the spinal cord, rather than within its parenchyma
Extradural: Located outside the dura
Most intradural tumors are benign and are usually meningiomas, schwannomas, neurofibromas, or myxopapillary ependymomas. Myxopapillary ependymomas occur most often in the cauda equina (1).
Most extradural tumors are metastatic. They usually originate as carcinomas of the lungs, breasts, prostate, kidneys, or thyroid or are sarcomas or hematologic malignancies, such as multiple myeloma or lymphoma.
Both intradural and extradural tumors exert their effects by compressing the spinal cord and its roots, rather than by invading the parenchyma. Most extradural tumors invade and destroy bone before compressing the spinal cord.
Reference
1. Koeller KK, Shih RY: Intradural extramedullary spinal neoplasms: Radiologic-pathologic correlation. Radiographics 39 (2):468–490, 2019. doi: 10.1148/rg.2019180200
Symptoms and Signs of Spinal Tumors
Spine tumors manifest with three defined pain syndromes:
Biologic (so-called)
Mechanical
Radiculopathy (radicular)
Biologic pain is typically the earliest symptom of all spinal tumors. The pain usually occurs at night or early in the morning and resolves with activity. It is thought to be caused by inflammatory mediators secreted by the tumor, which are influenced by the diurnal variation in endogenous corticosteroids secreted by the adrenal glands or by administration of exogenous corticosteroids.
Mechanical pain is caused by a spinal fracture and is worsened by movement or activity.
Radiculopathy (radicular pain) results from nerve root compression and follows the distribution of a nerve root.
Intradural extramedullary tumors may be painful when the nerve roots are compressed but can develop painlessly if the spinal cord is directly compressed without involving the root.
Neurologic deficits referable to the affected level of the spinal cord may 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.
Some patients with intradural tumors—most often meningiomas and schwannomas—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.
Diagnosis of Spinal Tumors
MRI
Patients with segmental neurologic deficits or suspected spinal cord compression require emergency diagnosis and treatment.
The following symptoms and signs may suggest spinal tumors:
Progressive, unexplained, or nocturnal back (ie, biologic) or radicular pain
Segmental neurologic deficits
Unexplained neurologic deficits referable to the spinal cord or nerve roots
Unexplained back pain in patients with a history of cancer
Diagnosis of spinal 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, compression fractures, destruction of the vertebral pedicles, or distortion of paraspinal tissues, especially if the tumor is metastatic.
Biopsy may be done to confirm the diagnosis.
Treatment of Spinal Tumors
Corticosteroids to prevent spinal cord compression
Excision, radiation therapy, or both
If patients have neurologic deficits due to spinal cord compression
Some well-localized primary spinal 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 surgical excision if radiation therapy is ineffective. For metastatic prostate cancer to the spinal vertebrae, antiandrogenic chemotherapy may be used as an adjunct to focal radiation.
Key Points
Spinal tumors may be intramedullary (within the cord parenchyma) or extramedullary (outside the parenchyma).
Extramedullary tumors may be intradural or extradural.
Most intradural tumors are benign meningiomas, schwannomas, and neurofibromas, which are the most common primary spinal tumors; most extradural tumors are metastatic.
Give corticosteroids to patients with neurologic deficits due to spinal cord compression.
Surgically excise spinal tumors and/or use radiation therapy.
