As a cancer progresses, it may spread, or metastasize, from the site in the body where it originated to secondary sites. When this occurs, the cancer is described as metastatic.
When a cancer metastasizes to the spine, it disrupts the healthy process of new bone cells replacing old bone cells. Existing bone is often destroyed, with either soft tissue or dense bone tumors growing where healthy bone should be. Metastatic spinal tumors are the most common type of malignant, or invasive, lesions in the spine.
What are the symptoms?
In cancer patients, back pain or numbness in the arms, legs, or elsewhere in the body are symptoms that may signal the presence of tumors caused by metastatic cancer in the spine.
As the tumor grows, it can cause severe pain, often characterized by an inability to find comfortable resting positions or spikes in pain when rising from or sitting down in a chair. This onset of pain is sometimes the first sign that the cancer has reached other areas of the body, as metastatic spinal tumors often lead to bone destruction and place pressure on the spinal cord.
Other common side effects of metastatic spinal tumors may be loss of appetite, nausea, or other symptoms caused by abnormally high blood calcium levels. This is the result of the tumor breaking down the bone and releasing increased levels of calcium into the bloodstream.
How common are metastatic spinal tumors?
Metastatic bone disease occurs in up to 85% of late-stage cancer patients with the three most common types of primary cancer – breast, prostate and lung.1 The spine is the most common site for bone metastases, with studies showing that 10% to 40% of all cancer patients will develop metastatic spinal tumors, with even higher rates in elderly patients.2 Several post-mortem studies have found metastatic spinal tumors in over 30% of all patients who died as a result of cancer and cancer-related causes.3,4
- Kurup AN and Callstrom MR. Ablation of skeletal metastases: Current status. J Vasc Interv Radiol. 2010;21:S242-S250.
- Cardoso ER, et al. Percutaneous tumor curettage and interstitial delivery of samarium-153 coupled with kyphoplasty for treatment of vertebral metastases. J. Neurosurg Spine 2009;10:336-342.
- Wong DA, Fornasier VL, and MacNab I. Spinal metastases: the obvious, the occult, and the impostors. Spine. 1990;15(1):1-4.
- Ortiz Gómez JA. The incidence of vertebral body metastases. Int Orthop. 1995;19:309-311.