The science with prostate cancer is continually evolving. While it is critical to have a solid partnership with your urologist, it's just as important that the facility that does your imaging has state of the art equipment. Keep in mind that modern equipment does not always equate to going to facilities that are considered to be a "top" according to a well-known magazine.
This technique uses a small probe inserted into the rectum to send sound waves into the prostate. The echo of the sound waves off the prostate is transformed into an image by a computer. TRUS is often used to measure the size of the prostate and as a guide for biopsy and some treatments.
MRI uses a magnetic field and radio waves to create a clear picture of the prostate. MRI scans are typically clearer and more useful than CT scans. MRI can be used to locate diseased tissue within the body and to precisely pinpoint cancerous cells. MRI can also be used to see if cancer has spread outside the prostate to nearby tissues. MRI images also help physicians to plan treatments such as surgery or radiation therapy.
While MRIs provide very sensitive imaging, the preferred technology for prostate imaging is the 3T (Tesla) MRI. Check out this page if you are having difficulty finding 3T MRI.
- Warning: Be advised that medical providers will request that contrast be used with the MRI. The contrast used is gadolinium -- a very dangerous metal that does not leave the body. You can request to do the MRI without contrast but be prepared for pushback. You will be told that "the MRI will be useless without the contrast." This is a false statement.
CT scans use x-rays to create a detailed, 3D cross-sectional image of the inside of the body. CT scans may be used to pinpoint the location of a tumor within the prostate, evaluate the extent of cancer, and assess whether the disease is responding to treatment. In some cases, CT technology is used to accurately guide cancer treatment during a procedure.
- Warning: Be advised that CT scans emit a very high dose of radiation to the body and should only be done when necessary. Radiation from scans accumulate in the body.
PET imaging uses a small amount of radioactive material, called a radiotracer, and a special camera to see inside the prostate. The specially designed radiotracer is injected into the patient and taken up by prostate cells, the radiotracer emits a small amount of energy which can be picked up by the PET scanner and is used to create a detailed image. This type of imaging can also identify abnormal functions in prostate cells that indicate cancer
PET Scans are usually done in combination with a CT or MRI scan.
PSMA stands for Prostate Specific Membrane Antigen and is a peptide (a very small protein) that is expressed on the surface of prostate cancer cells. PSMA-targeting molecules can show never-before-seen small bits of prostate cancer dispersed throughout the body. Then, attached to cancer-killing radiopharmaceutical drugs, they can be used to obliterate those spots of metastatic cancer.
This could be particularly helpful for men with an elevated PSA but a negative biopsy (or biopsies), or men considering Active Surveillance for prostate cancer. Men who are told they have low-grade disease – because the biopsy needle hasn’t picked up anything different – could have extra peace of mind if a PSMA-PET comes up negative for high-grade disease. Or, men who have had one or more inconclusive biopsies may decide to undergo surgery or radiation therapy if PSMA-PET shows high-grade cancer that the needles missed. Combining PSMA-PET with MRI may result in even more accurate and predictive scans, as well.
The Axumin PET scan works by detecting the metabolic activity of the cancer itself. Standard bone scans use calcium-related radioactive substances that concentrate in areas of the bone irritated by the cancer.
Axumin exploits the fact that prostate cancers absorb amino acids at a much more rapid pace than normal cells. Axumin consists of a radioactive tracer linked to an amino acid. Since the cancer cells absorb the amino acids more avidly than normal cells, the radiation concentrates inside the tumor cells. When the patient is placed under a scanner the location of high areas of radiation signal the location of the cancer in the patient’s body.
The Axumin scan is approved for men who have developed a rising PSA after previous radiation or surgery. Historically, simple bone scans and CAT scans required PSA levels in the 10 to 50 range before enough cancer would be present to be detected on a scan. The beauty of the Axumin PET scan is that it offers the possibility of detecting small metastatic lesions in the lymph nodes with PSA levels in the 1 to 10 range.
The other potential application of the Axumin scan, apart from its usefulness for determining the area of PSA relapse, is for men who have undergone chemo-hormonal treatment for advanced metastatic disease. After treatment, men may achieve a sharp reduction in PSA—perhaps from the 100s down to 10 or less. The Axumin scan can potentially single out an area of cancer in the body that is manifesting persistent metabolic activity, a sign that the cancer cells remain viable despite recent treatment with Lupron and Taxotere. If a relatively limited number of areas of persistent metabolic activity are detected, it is possible that such patients could benefit from spot radiation or other forms of treatment directed at the residual disease.
Choline C-11 PET scan is an imaging test used to help detect sites of prostate cancer that has returned despite treatment (recurrent prostate cancer). It may be used when other imaging hasn't been helpful. Choline C-11 PET scan is a positron emission tomography (PET) scan that uses a special chemical tracer called Choline C-11 Injection. A low-dose computerized tomography (CT) scan is usually done at the same time to help further show internal anatomy.
Choline C-11 PET scan may help doctors detect possible sites of recurrent prostate cancer that more-conventional imaging tests can't identify. Locating recurrent prostate cancer sooner may allow your doctor to identify small, isolated deposits of cancer — within the prostate and outside of the prostate — that can be targeted for more-effective treatment.
Choline C-11 PET scan uses a radioactive form of the vitamin choline. A small amount of the tracer is injected into a vein in your arm just before the scan is done. Prostate cancer cells in your body readily absorb the tracer. This can help doctors detect areas of prostate cancer cells throughout your body. A biopsy to remove some cells for lab testing is then done to confirm the presence of recurrent prostate cancer.