Tumors that originate in the spine (primary tumors) are quite rare. Primary spinal tumors tend to occur in younger adults and most typically are slow growing and benign. Most spinal tumors have spread (metastasized) from another area of the body. For patients with cancer elsewhere in the body, any new complaint of spine pain or neurological deficits requires an immediate evaluation to determine if the cancer has spread to the spine.
There are three common types of spinal tumors that can cause back pain: vertebral column tumors, intradural-extramedullary tumors, and intramedullary tumors.
1. Vertebral Column Primary tumors: These tumors occur in the vertebral column, and grow either from the bone or disc elements of the spine. They typically occur in younger adults. Osteogenic sarcoma (osteosarcoma) is the most common malignant bone tumor. Most primary spinal tumors are quite rare and usually grow slowly.
2. Intradural-Extramedullary Tumors: Intradural-Extramedullary (inside the dura) tumors grow within the spinal canal (under the membrane that covers the spinal cord) but outside of the nerves. Usually these tumors are benign and slow growing. However, they can cause symptoms of pain and weakness.
Most of these spinal tumors are:
Meningiomas that occur in the membranes surrounding the spinal cord and are usually benign but may be malignant. These tumors are more common in middle age and elderly women.
Nerve sheath tumors (schwannomas and neurofibromas) that arise from the nerve roots that come off the spinal cord. Again, this type of tumor is usually benign and slow growing, and it may be years before any neurological problems occur.
3. Intramedullary Tumors: Intramedullary tumors grow from inside the spinal cord or inside the individual nerves and often arise from the cells that provide physical support and insulation for the nervous system (glial cells). These tumors occur most often in the cervical spine (neck). They tend to be benign, but surgery to remove the tumor may be difficult.
The two most common types of intramedullary tumors are astrocytomas and ependymomas.