Prostate cancer remains the second most common cancer among men in the United States. One in eight men will be diagnosed with prostate cancer, with a projected 268,490 cases to be diagnosed in 2022. Due to early detection, effective treatments, and continued research, prostate cancer survivor rates are increasing each year.
Because of medical research, an innovative diagnostic method was recently approved for use in the U.S. One of the challenges of prostate cancer is that it can spread and metastasize in the lymph nodes, pelvis, and throughout the body. Detecting and locating these migrating tumors can make treatment difficult. However, the combination of a PET (positron emission tomography) scan and radioactive tracers has made it possible to pinpoint these areas anywhere in the body.
The way it works is a protein known as PSMA (prostate-specific membrane antigen) is found in high levels on the surface of most prostate cancer cells. A nuclear medicine physician injects a small amount of a radioactive tracer drug into the body that finds and latches on to the PSMA proteins. After injection, the patient waits an hour for the tracer to travel through the body. Once the drug has bonded to the PSMA prostate cell, it “lights up” and can be seen using a PET scan. These unprecedented images allow doctors to find and treat tumors that are only a few millimeters in size anywhere in the body.
Currently, two FDA-approved radioactive tracer drugs are available in the U.S. The first, known as 68Ga-PSMA-11, was approved in 2020 and is manufactured and used by UCLA Health and UC San Francisco. The second was developed by John Hopkins University and was recently approved at the end of 2021. This radioactive tracer drug, known as 18F-DCFPyL or PyL for short, has been approved for commercial use. This makes its use more widely available for prostate cancer patients under the trade name PYLARIFY®. There is a negligible difference between the two drugs. The radioactive tracer is well-tolerated by most patients, and once the tracer has latched to the cell, it disappears without doing anything further to the body.
Who Should Consider a PSMA PET Scan
A PSMA PET scan is more responsive than standard imaging like CT or bone scans in pinpointing areas of prostate cancer within the body. These scans are a viable treatment option as part of a comprehensive, personalized care plan determined by a physician and patient. Currently, patients who should consider a PSMA PET scan are:
- Men who have been recently diagnosed with prostate cancer and are at risk of the cancer spreading
- Men previously treated for prostate cancer, usually with radiation therapy or surgery, and have a recurrence of rising PSA (prostate-specific antigen) levels.
Future of Prostate Cancer Treatment
More research is underway in Europe, Australia, and other international clinical trials on PSMA-targeting radionuclides, such as 177Lu-PSMA-617. The idea is to use the radionuclides to target and kill cancer cells using the same method as the radioactive tracer drug. The benefit is that this brings a localized fight to cancer cells while leaving nearby cells undamaged and healthy. Research is also being done on other molecules and therapies to target the “PSMA-invisible” forms of prostate cancer.
Early detection screening of prostate cancer is currently conducted through a PSA test that measures the levels of PSA in the blood. The most common risk factors for prostate cancer are:
- Personal history
- Family history, including a history of breast, ovarian, or pancreatic cancer
African-American men are more likely to be diagnosed with prostate cancer than other men and diagnosed at a younger age.