New guidelines, tools for prostate cancer screening
June is Men's Health Month
June 1, 2018
Men age 50 and older and living in Alaska should discuss blood testing for prostate cancer with their physicians. The guidelines are now changing because of concerns that some men who could benefit from screening are not getting screened.
The U.S. Preventive Services Task Force (USPSTF) now recommends that men 55 to 69 who are interested in screening talk to their doctors about potential benefits and harms of screening for prostate cancer before deciding whether to undergo periodic prostate-specific antigen (PSA)-based screening. The USPSTF recommends against PSA-based screening for men 70 and older. This is a significant change from the previous recommendation.
The USPSTF routinely makes recommendations about the effectiveness of preventive care services. This latest statement is an update of the 2012 recommendation. Prostate cancer is one of the most common types of cancer that affects men. Many men with prostate cancer never experience symptoms and without screening would never know they have the disease.
Screening offers a small potential benefit of reducing the chance of death from prostate cancer in some men. However, many men will experience potential harms of screening, including false-positive results that require additional testing and possible prostate biopsy. Other harms include overdiagnosis and overtreatment as well as complications, such as incontinence and erectile dysfunction.
In determining whether PSA screening is appropriate in individual cases, patients and clinicians should consider the balance of benefits and harms on the basis of family history, race/ethnicity, comorbid medical conditions, patient values about the benefits and harms of screening and treatment-specific outcomes, and other health needs, according to the new guidelines.
“The previous guidelines stated that there should be no screening and most oncology specialists, including urologists, felt this to be misguided, fearing that without screening we would see patients presenting with more advanced disease. Some data have corroborated this,” said Dr. Rick Lee, who is a medical Oncologist at Massachusetts General Hospital Cancer Center. “I think this new set of guidelines is a good thing and was needed. Now, at least for patients between 55 and 69, PSA screening should be considered as a point of discussion between patient and physician.”
In the United States, the lifetime risk of being diagnosed with prostate cancer is approximately 13 percent, and the lifetime risk of dying of prostate cancer is 2.5 percent. The median age of death from prostate cancer is 80 years. African American men and men with a family history of prostate cancer have an increased risk of prostate cancer compared with other men. Adequate evidence from randomized clinical trials shows that PSA-based screening programs in men age 55 to 69 years may prevent approximately 1.3 deaths from prostate cancer over approximately 13 years per 1,000 men screened. Screening programs may also prevent approximately 3 cases of metastatic (spreads outside of the prostate) prostate cancer per 1,000 men screened.
“Prostate cancer remains the most commonly diagnosed cancer in American men. While we can debate the data on whether screening saves lives, and the European study showed this to be true, I think that putting the screening question back into the discussion between a man and his primary care physician is appropriate,” Dr. Lee told Senior Voice.
Better screening tools
A team of researchers from Cleveland Clinic is reporting that a new blood test known as IsoPSA detects prostate cancer more precisely than current tests in two crucial measures. They found this new test can distinguish prostate cancer from benign conditions and identify patients with high-risk disease. By identifying molecular changes in the PSA protein it may be possible to substantially reduce the need for biopsy, and may thus lower the likelihood of overdetection and overtreatment of nonlethal prostate cancer.
The researchers conducted a multicenter prospective study and directly compared the clinical performance of IsoPSA to PSA with patients already scheduled for prostate biopsy. IsoPSA proved significantly superior in discriminating between prostate cancer and benign conditions and identifying patients with high-grade disease. The results show that if validated and adopted on a widespread basis, IsoPSA could significantly reduce the rate of unnecessary biopsies by almost 50 percent, according to the researchers.
Other investigators are now testing a urine test for prostate cancer. A team of researchers has been investigating a new class 3-gene expression urine assay for prostate cancer. It is called ExoDx Prostate IntelliScore (EPI) and it may help identify patients with higher grade disease and could help reduce unnecessary biopsies.
The researchers tested it in 504 men. The average age of the men was 64 years and the average PSA level was 5.6 ng/mL. The researchers found that 53 percent of the men had a positive biopsy. The urine test was much more predictive than standard screening for discriminating high-grade disease from low-risk/benign disease. Using this urine test, it theoretically could cut biopsy rates by up 40 percent.