Overview
Neoplasms of the spine can be categorized as primary tumors or metastatic tumors. Metastatic is a general term used to describe the spread of a cancer from some other location in the body. The spinal column is one of the most common sites for cancer to metastasize (spread) to. Metastatic tumors of the spine are the most common tumors of the spine, and are routinely treated without surgery unless there is resultant spinal instability or neurologic compromise. The majority of metastatic lesions are treated with chemotherapy and/or radiation therapy that is specific for the primary cancer type. Primary tumors of the spine can be benign or malignant (cancer), and can be further subdivided into intradural and extradural neoplasms. Intradural means that the tumor is arising from or within the dural sac (sac containing the spinal cord and nerves). Extradural tumors are often neoplasms infiltrating the bony structure of the vertebrae, but can also arise within the epidural space. Intradural tumors are further classified as intramedullary or extramedullary, and indicate whether or not a tumor is arising from within the spinal cord itself (intradural-intramedullary), or from the coverings of the spinal cord (intradural-extramedullary). Overall, primary spine tumors are rare and comprise approximately .04% of all tumors and 10% of all bone tumors.
Extradural Tumors
Benign
- Osteochondroma
- Osteoid Osteoma
- Osteobalstoma
- Aneurysmal Bone Cyst
- Hemangioma
- Giant Cell Tumor
- Eosinophilic Granuloma
- Angiolipoma
Malignant
- Multiple Myeloma
- Solitary Plasmacytoma
- Osteosarcoma
- Chondrosarcoma
- Ewing’s Sarcoma
- Chordoma
- Lymphoma
Intradural-Extramedullary Tumors
- Meningioma
- Neurofibroma
- Schwannoma
- Ependymomas
Intradural-Intramedullary Tumors
- Astrocytoma
- Ependymoma
- Hemangioblastoma
- Lipoma
- Dermoid
- Epidermoid
- Teratoma
- Neuroblastoma
- Oligodendrolioma
- Cholesteatoma
- Subependymoma
- PNET
Causes
Neoplasms and cancer are defined as an abnormal cellular response that causes cells to grow at an uncontrolled rate, or in an abnormal location, or both. The underlying cause of cancer and tumors is often unknown. At times, patients with known exposure to a cancer-causing agent may be identified (asbestos, radiation, etc). Cancer is known to spread to the spinal column frequently, and occurs through the bloodstream or the lymphatic system.
Symptoms
Neck pain is the most common presenting symptom of patients with a cervical spine tumor. Patients often have unrelenting pain, as well as night pain, that is not relieved by rest or traditional measures. Patients may have neck stiffness and decreased range-of-motion. Patients may have weakness or numbness if the tumor is advanced and causing neurologic compression or irritation. In addition, patients may have constitutional symptoms such as low-grade fever, night sweats, fatigue, malaise, and/or loss of appetite, among others.
Physical Findings
The physical findings for patients with a spine tumor are limited. Patients may demonstrate tenderness and spasm with decreased cervical range-of motion, but not routinely. The neurologic examination will generally be normal unless the spinal tumor is advanced and causing neurologic compression or irritation.
Imaging Studies
Plain x-rays of the cervical spine allow the clinician to assess the overall spinal alignment and bony integrity, and may demonstrate a bone-forming or bone-destroying neoplasm if the lesion is large enough. A magnetic resonance imaging test (MRI) with gadolinium is often recommended and required to accurate define the size and extent of the neoplasm, and whether it has spread into spinal canal. Spine tumors can be differentiated from pyogenic spine infections because neoplasms affect the vertebral body primarily and usually do not affect the disc, whereas pyogenic vertebral osteomyelitis preferentially destroys the endplate and intervertebral disc. A computed tomography (CT) scan may also be ordered as it allows clinicians to better visualize details of the bony anatomy better than an MRI test. A CT-myelogram (dye is injected within the thecal sac) may provide additional diagnostic information, especially when evaluating intradural neoplasms. A bone scan is a test frequently ordered when cancer is suspected, and can determine if there are other lesions in the bones throughout the entire body.
Laboratory Tests
Laboratory tests are often ordered when a neoplastic work-up is undertaken. A complete blood count (CBC) with differential, metabolic panel, serum protein electrophoresis (SPEP), urine protein electrophoresis (UPEP), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) tests are routinely ordered when evaluating a tumor. Laboratory tests may confirm the diagnosis of lymphoma, leukemia, multiple myeloma, or infection. A PPD skin test should also be placed to test for tuberculosis, which can mimic a spinal tumor.
Diagnosis
The diagnosis of a spine tumor may be delayed, primarily because the early signs and symptoms are subtle and clinicians do not initially suspect it. Patients with “red flags” (symptoms suggesting infection or tumor, such as unrelenting pain, night pain, fevers, chills, night sweats, weight loss, etc) must be appropriately evaluated with imaging and laboratory tests to confirm the diagnosis.
Treatment Options
The treatment of a neoplasm of the cervical spine depends on a number of factors: the patient’s age and associated medical conditions, the type, grade, and stage of the neoplasm, the severity of a patient’s symptoms, and the severity of neurologic compression and bony destruction. In comparison to the thoracolumbar spine, metastatic tumors of the cervical spine are more likely to cause instability and/or neurologic compromise and are more often treated surgically. Benign primary bone tumors are often treated by surgical tumor resection; however, some benign tumors may be treated conservatively and observed if there is minimal pain and there is no evidence of spinal instability or neurologic compression. Malignant primary spine tumors are often treated by surgical resection and adjuvant chemotherapy and/or radiation. Surgical treatment often includes neurologic decompression, fusion, and instrumentation in addition to tumor resection. An anterior or posterior surgical approach, or at times a combined approach, may be utilized depending on where the tumor is located and where the neurologic compression is most prominent.
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