What does prostate cancer screening consist of? Prostate cancer is a common form of cancer among men. Prostate cancer usually has no symptoms in the early stages, but screening can help detect it while the disease is still treatable. Screening tests look for markers — these are abnormal levels of proteins and other substances that can indicate the presence of cancer. According to the American Cancer Society (ACS), 1 in 9 men are diagnosed with prostate cancer. In most cases, effective treatment is available. For those patients who receive the diagnosis in the early stages of the disease, there is a significantly greater chance of a cure. Current tests to detect prostate cancer include the prostate-specific antigen (PSA) blood test, which tests for high levels of the PSA protein. However, this test can sometimes produce a false-positive result, meaning that the test shows a positive result when there is no prostate cancer. This can lead to anxiety and unnecessary additional tests. For this reason, scientists have been looking for other reliable markers for prostate cancer screening. Testing for a substance called prostate cancer antigen 3 (PCA3) can be an alternative diagnostic method for detecting prostate cancer. What are the problems with current prostate cancer screening methods? It is recommended that men at average risk of developing prostate cancer start screening for it from age 50. Men at higher risk should start screening earlier. Currently, the standard way to screen for prostate cancer is the PSA (prostate-specific antigen) blood test. High PSA levels can indicate prostate cancer, but they can also indicate other conditions. This is because both cancerous and healthy cells in the prostate gland can produce PSA. Other factors that can affect PSA levels include: Age, higher PSA levels are more commonly found in older men; Large prostate gland; Enlarged prostate or benign prostatic hyperplasia; Inflammation or infection, such as prostatitis or a urinary tract infection; Stimulation of the prostate, which can occur during a digital rectal examination (the prostate gland is felt through the wall of the rectum); Constipation; Medicines, some of which raise PSA levels and others lower them. If the test shows that PSA levels are high, a biopsy will most likely be performed to test for cancer. Prostate biopsy is an invasive procedure and can lead to anxiety, discomfort and possible complications. Some studies have noted that routine PSA testing can lead to overdiagnosis (a side effect of the drive for early detection) of prostate cancer by 20-50%. This can lead to physical and emotional risks of getting a false positive result,which can lead to unnecessary biopsies and even treatment. Although testing PSA blood levels can save lives, it’s a good idea for men aged 55-69 to make the decision to get tested after talking with their doctor. The US Preventive Services Task Force (USPSTF) does not recommend PSA screening for men over the age of 70. Also, experts have not agreed on what “normal” PSA levels should be. A 2004 study, for example, found that doctors overdiagnosed some high-grade prostate cancers in men with normal PSA levels. According to the National Cancer Institute (NCI), there is no clear consensus on the optimal PSA threshold for recommending prostate biopsy for men of any ethnic group. The PCA3 test can help a doctor decide whether to order a biopsy in a person with high PSA levels. What is the PCA3 test for prostate cancer? The PCA3 test may be one way to get more accurate prostate cancer screening results. PCA3 is a gene that is present in all cells of the prostate gland. It causes these cells to produce small amounts of certain proteins. This type of protein is also present in urine. Cancerous prostate cells can produce 60-100 times more of this protein than non-cancerous cells. When this happens, the extra protein ends up in the urine. If tests detect this protein in the urine, it can signal the presence of prostate cancer. Initial studies show that these proteins are present in about 95% of prostate cancer samples. They are also more likely to be present in high levels in cancerous tissue compared to benign tissue. In other words, a patient who does not have prostate cancer is unlikely to have significant amounts of this protein. Therefore, the PCA3 test may be useful when PSA test results are abnormal. The advantage of the PCA3 test is that conditions unrelated to prostate cancer do not affect PCA3 levels. While high PSA levels can indicate cancer, they can also be the result of other factors � ranging from advanced age to infection. The authors of a 2015 study involving 407 men concluded that the PCA3 test may be useful both as a diagnostic tool and in determining the prognosis of prostate cancer. Scientists have found that a PCA3 test is more likely to show a correct diagnosis of prostate cancer than two types of PSA test. In addition, patients with more aggressive tumors more often had higher PCA3 test scores. The Gleason score is one way of describing the classification of cancer cells. What can be expected from the PCA3 test for prostate cancer? No special patient preparation is required before undergoing the PCA3 test,but knowing what to expect can help put his mind at ease. There are two parts to the PCA3 test: Rectal examination. First, a specialist performs a digital rectal examination. In addition to feeling lumps or other changes, the doctor may also massage the prostate, this encourages more PCA3 proteins to enter the urine before the next part of the test; Urine examination. Immediately after that, the patient must provide a urine sample, which the doctor sends to a laboratory for analysis. Test results should be available within a few days. Depending on the results of the PCA3 test, the doctor may recommend: Continue routine screening if the result is negative; Adopting a “watch and wait” approach, with testing at intervals to see if results change; Additional tests to confirm the presence of cancer cells. Additional tests may include: Prostate biopsy, which means taking a tissue sample from the prostate, where its cells are examined in a laboratory; Transrectal prostate ultrasound; Magnetic resonance imaging (MRI) of the prostate gland to look for prostate masses. The PCA3 test is not currently a standard test for prostate cancer. However, a urologist may prescribe it when the initial PSA test result gives abnormal results. This test remains a relatively new screening method for prostate cancer and its use is not yet widespread, but it may be a promising diagnostic tool in the future. Scientific researchers are looking for ways to combine the PCA3 test with other tests for a more accurate result during prostate cancer screening. References: 1. American Cancer Society (ACS). American Cancer Society recommendations for prostate cancer early detection 2. National Center for Biotechnology Information (NCBI). Chunhua, L., et al. (2018). Clinical significance of peripheral blood PCA3 gene expression in early diagnosis of prostate cancer 3. National Center for Biotechnology Information (NCBI). Merola, R., et al. (2015). PCA3 in prostate cancer and tumor aggressiveness detection on 407 high-risk patients: A National Cancer Institute experience 4. Medical News Today. All you need to know about the PCA3 testto see if results change; Additional tests to confirm the presence of cancer cells. Additional tests may include: Prostate biopsy, which means taking a tissue sample from the prostate, where its cells are examined in a laboratory; Transrectal prostate ultrasound; Magnetic resonance imaging (MRI) of the prostate gland to look for prostate masses. The PCA3 test is not currently a standard test for prostate cancer. However, a urologist may prescribe it when the initial PSA test result gives abnormal results. This test remains a relatively new screening method for prostate cancer and its use is not yet widespread, but it may be a promising diagnostic tool in the future. Scientific researchers are looking for ways to combine the PCA3 test with other tests for a more accurate result during prostate cancer screening. References: 1. American Cancer Society (ACS). American Cancer Society recommendations for prostate cancer early detection 2. National Center for Biotechnology Information (NCBI). Chunhua, L., et al. (2018). Clinical significance of peripheral blood PCA3 gene expression in early diagnosis of prostate cancer 3. National Center for Biotechnology Information (NCBI). Merola, R., et al. (2015). PCA3 in prostate cancer and tumor aggressiveness detection on 407 high-risk patients: A National Cancer Institute experience 4. Medical News Today. All you need to know about the PCA3 testto see if results change; Additional tests to confirm the presence of cancer cells. Additional tests may include: Prostate biopsy, which means taking a tissue sample from the prostate, where its cells are examined in a laboratory; Transrectal prostate ultrasound; Magnetic resonance imaging (MRI) of the prostate gland to look for prostate masses. The PCA3 test is not currently a standard test for prostate cancer. However, a urologist may prescribe it when the initial PSA test result gives abnormal results. This test remains a relatively new screening method for prostate cancer and its use is not yet widespread, but it may be a promising diagnostic tool in the future. Scientific researchers are looking for ways to combine the PCA3 test with other tests for a more accurate result during prostate cancer screening. References: 1. American Cancer Society (ACS). American Cancer Society recommendations for prostate cancer early detection 2. National Center for Biotechnology Information (NCBI). Chunhua, L., et al. (2018). Clinical significance of peripheral blood PCA3 gene expression in early diagnosis of prostate cancer 3. National Center for Biotechnology Information (NCBI). Merola, R., et al. (2015). PCA3 in prostate cancer and tumor aggressiveness detection on 407 high-risk patients: A National Cancer Institute experience 4. Medical News Today. All you need to know about the PCA3 testA National Cancer Institute experience 4. Medical News Today. All you need to know about the PCA3 testA National Cancer Institute experience 4. Medical News Today. All you need to know about the PCA3 test