A New Test for Improved Detection of Prostate Cancer: PSMA (Prostate-Specific Membrane Antigen) PET Scan
A new type of scan is helping doctors at The Harold Leever Regional Cancer Center detect very small, hard-to-find areas of prostate cancer, which could lead to better treatment outcomes.
Prostate cancer is the most common type of cancer in men, other than skin cancer. According to the American Cancer Society, approximately 268,490 new cases of prostate cancer will be diagnosed in 2022.
While prostate cancer can be a serious disease, most men diagnosed with prostate cancer do not die from it. In fact, the prognosis for prostate cancer is among the best for all cancers. For prostate cancer that has not spread to other parts of the body, the five-year relative survival rate (how likely the person is to live five years compared to someone who has not been diagnosed with cancer) can be as high as 99%, with a 15-year survival rate around 95%.
The prognosis isn’t as good for cases where the cancer has spread significantly, so it’s important to catch prostate cancer—both the initial disease and the spread to other parts of the body—as early as possible.
The Leever Cancer Center is now using a new, more sensitive biomarker for PET/CT scans for prostate cancer. A biomarker is a liquid that is injected into the patient and searches the body looking for specific cancer cells. There are a number of different biomarkers for different types of cancer.
The new prostate cancer biomarker is called Pylarify (Piflufolastat F 18) which seeks out the Prostate-Specific Membrane Antigen (PSMA) within prostate tumor cells and makes them visible in a PET/CT scan. Imaging with PSMA has been shown to detect prostate cancer cells missed by other scan types, such as CT, MRI, or bone scans.
Who Should Get a PSMA Scan?
This new test is used in two different scenarios. In the first scenario, the scan is used for patients who have already been diagnosed with prostate cancer and received some type of treatment, but who have shown a rising PSA level indicating that the cancer has come back. In those cases, a PSMA scan can identify where in the body the new or remaining prostate cancer cells are located, and allow for targeted treatment in those areas.
“Knowing where the disease is allows me to escalate my radiation dose for the patient, which will increase the curative value,” said Dr. Joseph Ravalese, III, a radiation oncologist at The Harold Leever Regional Cancer Center. “And knowing the exact location of the disease makes the treatment safer, since we can target the specific area and minimize the radiation dose to surrounding tissues.”
In the second scenario, the scan is used for initial staging of prostate cancer. This allows for a more accurate prostate cancer staging, which in turn directs the type of treatment the patient will receive.
For patients with prostate cancer that has not spread to other parts of the body, there are six risk groups: very low risk, low risk, intermediate risk- favorable, intermediate risk-unfavorable, high risk, and very high risk. Dr. Ravalese, in conjunction with the national guidelines, favors using the test for anyone in the intermediate risk-unfavorable group or higher.
“What I’ve found with patients who have received the scan for initial staging is that we are finding disease we did not expect to see—in the lymph nodes and even bone,” said Dr. Ravalese. “This allows us to do more aggressive and tailored treatments for the patient.”
How to Prepare for the PSMA
There is no prep for this type of scan. You will be asked to sit quietly for one hour after your injection, then you will empty your bladder before the scan, which takes 20 to 30 minutes.
Once your images are complete, the technologist will forward them to the reading radiologist, who will send a final report to the doctor who ordered the test for you. Your doctor should be ready to review the results with you within 48 hours.
It is important to note that this test is perfectly safe. There is a small amount of radioactivity in the injection you receive, so we recommend staying at least five feet away from anyone who is pregnant or under age 12 to avoid exposing them to any residual radiation. All radioactivity will be gone by the day after your scan, and you may resume normal activities. There are no known side effects to PSMA.
The new test has really changed our ability to address where the disease is in the patient and how to treat it appropriately. It allows us to tailor the therapy specifically for that individual to get the best result.
Joseph Ravalese, III, MD, Radiation Oncologist, The Harold Leever Regional Cancer Center
If you have any questions or concerns about PSMA or PET/CT or if PSMA has been recommended for you or a loved one, our radiology staff is available to answer any of your questions. Our goal is to keep you comfortable and relaxed while giving the radiologist a top-quality image to help with your diagnosis and treatment.