A single-photon emission computerized tomography (SPECT) scan creates three-dimensional images of your internal organs that reveal both anatomy and function.
A SPECT scan by itself can't confirm a diagnosis of cancer. But it can help determine the extent to which cancer has spread or help diagnose an abnormality found on another type of imaging study. The only way to definitively diagnose cancer is by removing a small piece of tissue (biopsy) for examination under a microscope.
A SPECT scan can help detect cancer with the aid of cancer-seeking radioactive tracers. Your doctor injects a tiny amount of radioactive tracers through a vein in your arm. A special camera — which detects the radiation emitted by these tracers — rotates around you, creating images of your body from all different angles. Tumors often absorb more of the tracers than healthy tissue. This allows tumors to appear on the scan.
A SPECT scan can help detect:
- Some specific types of cancer, such as neuroendocrine tumors, which can be difficult to find with standard computerized tomography (CT) scans
- Cancer that has spread to the bone
Other uses of SPECT scans include:
- Identifying brain abnormalities in people who have seizures
- Helping to confirm a diagnosis of Alzheimer's disease
- Finding the location of an infection