Metastatic Spinal Tumor

The spread of any cancer is called metastasis. A metastatic tumor is one that has spread from cancer in another part of the body. A metastatic spinal tumor, therefore, is a tumor that first started in another place in the body and spread to the spine.

A metastatic tumor is sometimes called a secondary tumor. The original tumor, located elsewhere in the body, is called the primary tumor. The metastatic spinal tumor grows in the spine, but it is composed of cells from the primary tumor.

Metastatic spinal tumors tend to occur in the vertebrae, or bones of the spine. In some cases, only a single vertebra is involved, but in many cases, two or more vertebrae are involved. Most metastatic spinal tumors occur in the thoracic spine, in the upper and mid-back.

Symptoms

Symptoms of a metastatic spinal tumor depend on the tumor’s size and location. A substantial minority cause no symptoms at all.

As metastatic spinal tumors grow, they may weaken the vertebrae. A compression fracture may eventually occur in the weakened vertebrae. In some cases, a compression fracture is the first symptom of a metastatic spinal tumor.

Sometimes these tumors cause pain as they grow. This pain is usually described as an aching pain in the bones that is not relieved by rest. (In fact, the pain is often worse during the night or upon waking in the morning.)

If the growing tumor compresses the spinal cord or nerve roots, it may cause problems with movement or sensation (clumsiness, numbness, pins-and-needles) in the arms or legs. In severe cases, bowel or bladder control may be compromised.

Diagnosis

  • X-ray (also known as plain films): test that uses invisible electromagnetic energy beams (X-rays) to produce images of bones. Soft tissue structures such as the spinal cord, spinal nerves, the disc, and ligaments are usually not seen on X-rays, nor on most tumors, vascular malformations, or cysts. X-rays provide an overall assessment of the bone anatomy as well as the curvature and alignment of the vertebral column. Spinal dislocation or slippage (also known as spondylolisthesis), kyphosis, scoliosis, as well as local and overall spine balance can be assessed with X-rays. Specific bony abnormalities such as bone spurs, disc space narrowing, vertebral body fracture, collapse, or erosion can also be identified on plain film X-rays. Dynamic, or flexion/extension X-rays (X-rays that show the spine in motion) may be obtained to see if there is any abnormal or excessive movement or instability in the spine at the affected levels.
  • CT scans (computed tomography scans, or CAT scans) use a combination of X-rays and computer technology to produce detailed images of the body. CT scans are more detailed than general X-rays; these scans can reveal both bones and tumors.
  • MR (magnetic resonance) scans use a combination of large magnets, radio waves, and a computer to produce detailed images of organs and structures inside the body. MR scans show tumors most accurately.

A more thorough evaluation may sometimes be necessary to identify the primary site of the tumor and/or other possible secondary tumors. Such evaluations may include a detailed health history and physical exam, lab work (blood tests), bone scan, PET (positron emission tomography) scan, CT of the chest, and a percutaneous biopsy in which a needle is inserted into the tumor through the skin.

Risk Factors

Common primary tumors for spinal metastasis are lung, breast, and prostate cancers. Cells that break off from these tumors travel through the body, usually through the bloodstream. Many of these cells will die, but some may lodge and grow in a new location, such as the bones of the spine.

The spine is the most common site of bone metastasis. Overall, bone is the third most common site for metastasis. Only the lung and the liver are more common.

Treatments

Spinal metastasis is a result of a cancer that has spread, so treating the spinal tumor itself will not cure the cancer. However, there are many treatments available to shrink the tumor or slow or stop its growth, relieve pain or neurological symptoms caused by the tumor, and maintain the stability of the spine.

Depending on the type of tumor, radiation therapy and chemotherapy may be used to slow, stop, or shrink it.

Oral medications, including analgesics, anti-inflammatory, and neuropathic medications, can help treat nerve pain. Steroid treatment may help relieve bone pain.

Surgical removal of metastatic spinal tumors can rapidly and effectively relieve pressure on the spinal cord or nerve roots. This generally provides relief from neurological symptoms like radiating pain, numbness, weakness, clumsiness, etc. If the tumor compromises the stability of the spine, surgery to stabilize the spine with metallic implants may be useful.