Imaging Tests for the Prostate
To identify cancer, you may need tests with scanning machines that produce images of your body. A radiologist will interpret these images to understand the precise location and size of a tumor. Imaging tests may include:
An ultrasound uses high-frequency sound waves to create images. An ultrasound does not use radiation and is painless. It can provide clear images of your prostate gland tissues. An ultrasound can:
- Show greater detail of abnormal areas
- Distinguish between different types of tissues, such as fluid-filled cysts and solid masses
- Help guide a biopsy needle to take a tissue sample and test for cancer
Magnetic resonance imaging (MRI) uses radio waves and a powerful magnetic field to create detailed, cross-sectional pictures of the prostate. MRI does not use radiation. At Stanford, your doctors may fuse the MRI images with the ultrasound images to create a more precise map of the prostate gland to help improve the accuracy of biopsy.
A bone scan can rule out whether prostate cancer has spread to your bones. Also called skeletal scintigraphy, the test uses a small amount of radioactive material to highlight any abnormal tissue, which may indicate cancer. Your doctor may recommend a bone scan if you are diagnosed with an invasive type of prostate cancer.
PET and CT scans
A positron emission tomography (PET) scan is a nuclear imaging test that uses a small amount of radioactive material to highlight areas of suspicious cells. Computed tomography (CT) scans use X-ray technology to take cross-sectional images of the body. We use these technologies alone or combined, depending on the information we need from the scans. During treatment for prostate cancer, our doctors use PET scans alone to:
- Determine whether cancer has spread to the lymph nodes (small glands that filter bacteria, viruses, cancer cells, and other impurities) or other parts of the body and, if so, where
- Monitor how well cancer is responding to treatment
- See if cancer has returned after treatment
We rarely use CT scans alone to evaluate cancer in the prostate. CT is helpful in examining other areas of the body to see if prostate cancer has spread.
We offer combined PET/CT scanning, which takes both scans at the same time and in the same machine to keep you in the same position. This technique allows us to combine CT images of the body with PET scans that highlight possible areas of cancer.
The combined PET/CT images show the specific locations of any cancer, providing more precise information for treatment. We use PET/CT scans to:
- Stage prostate cancer
- Check other parts of the body to see if cancer has spread
- Monitor cancer’s response to treatment
Bone mineral density test
Your doctor may recommend a bone mineral density test before treatment for prostate cancer. Prostate cancer treatment can put you at a higher risk for developing osteoporosis, a condition that causes bone loss and fragile, brittle bones. Measuring your bone mineral density before treatment gives us a baseline, so we can compare later test results with initial bone loss.