Spinal cancer is the destructive, uncontrolled growth and reproduction of malfunctioning cells in the spinal cord. A group of such cells, called a malignant neoplasm or malignant tumor, will grow and spread into healthy neighboring tissues, destroying them. Spinal cancer can cause symptoms such as weakness, back pain, and paralysis and can eventually be fatal. It is most commonly treated by surgical removal of the tumor followed by radiation therapy, though radiation alone may be used if the risk of nerve damage from surgery is unacceptably high.
Normal, healthy cells have biological mechanisms encoded in their DNA that control their life cycle so that they can function as part of a larger whole. Some of these processes regulate how frequently a cell undergoes mitosis, in which the cell reproduces itself by making a copy of its genetic code and splitting in two. Others govern the programmed death of cells, called apoptosis, that causes damaged or defective cells to shut themselves down. Like all cancers, spinal cancer is the result of genetic damage to a cell that disrupts these processes, resulting in unconstrained growth without regard to the health of the organism as a whole.
Spinal cancer is usually the result of cancer that started elsewhere in the body and subsequently spread to other locations via the bloodstream or lymph system, a process called metastasis. It is also possible for cells in the bones or bone marrow of the spinal cord to become malignant on their own, but this is much less common. Metastatic cancers originating in the breast, lungs, or prostate are common sources of metastatic spinal tumors. Most malignant spinal tumors are extradural, which means that they are located outside of the membranes that surround the spinal cord and brain.
Spinal cancer can produce a number of symptoms, mostly due to the damage suffered by the nervous system as the disease spreads. In addition to pain in the damaged tissues of the spine itself, the presence of the malignant neoplasm can cause pain elsewhere as its growth puts pressure on the vertebrae and compresses major nerves connecting the central nervous system to other parts of the body. This can also cause the sufferer to become weaker by interfering with nerve impulses to the muscles or dull his or her sense of touch in a similar manner by disrupting sensory signals. If sufficiently advanced, spinal cancer can cause total paralysis in this way. It can also cause incontinence if the growth of the tumor compresses the nerves connecting to the bowels or the bladder.