Diagnosing a metastatic spinal tumor is a multi-step process that involves taking a thorough history, past medical history, review of systems and then a comprehensive physical examination. Based on the information gleaned, imaging, biopsy, and/or blood tests may be obtained. Typically, a biopsy is required to make a final diagnosis unless the patient’s history or other tests make clear which cancer type has spread.
Metastatic Spinal Tumor Imaging
Several imaging technologies are available to help determine a tumor’s location and size.
Computed Tomography (CT Scan)
CT scans clearly differentiate bone from soft tissue (such as a tumor). These scans use special x-ray equipment and computer software to enhance images. A CT with myelogram uses contrast dye to better view soft tissues, such as tumors.
Magnetic Resonance Imaging (MRI Scan)
An MRI is the most common imaging modality for visualizing spinal tumors. It provides accurate information about the soft tissues and bony structures of the spine using magnetic field energy to create images. Because of the magnetic energy, patients with certain types of metal implants or other devices (such as a pacemaker) cannot have an MRI and are prescribed a CT scan with myelogram instead.
Positron Emission Tomography (PET) Scan
A PET scan involves injecting a small amount of radioactive tracers into the patient’s bloodstream. Then a special camera is used to locate areas where the radioactive tracers have collected in the body. These areas are more likely to be tumor cells.
A bone scan is useful for finding subtle bone changes, such as the growth of a tumor. This scan uses a radioactive tracer that is injected into the bloodstream and absorbed by the bones. A special camera can then identify hot spots that show abnormalities in the bones. Another benefit of a bone scan is that it can scan the entire body, which may be helpful in finding tumors that may have spread elsewhere.1
Metastatic Spinal Tumor Biopsy
A biopsy involves extracting a tissue sample from the tumor so that it can be examined by a pathologist for possible cancer. In most cases, percutaneous needle biopsy is used, meaning that the needle in inserted through the skin and it is not an open surgical procedure. The results of the biopsy are used to help determine which treatment is best for each patient. For example, different treatment options may be considered depending on the cancer type.
While open biopsy is another option, it is generally not required for metastatic spinal tumors.
Blood tests may also be part of the diagnostic process for metastatic spinal tumors. In addition to confirming cancer, a blood test may also identify where the cancer came from, such as the breast or prostate.