In the wake of changing guidelines related to prostate cancer screening, a newly published review article out of University Hospitals Case Medical Center's Seidman Cancer Center in Cleveland provides important guidance about the prostate specific antigen (PSA) test. The peer-reviewed article, titled Prostate Cancer Screening and the Associated Controversy, was published in the October issue of Surgical Clinics of North America.
The team conducted a thorough review of recent large-scale studies and assessed the impact of shifting guidelines related to PSA screening, which measures levels of PSA in the blood. Lead authors Robert Abouassaly, MD, William Tabayoyong, MD, PhD, and colleagues found that active surveillance can reduce the harms of overtreatment in prostate cancer.
"While PSA screening has reduced prostate cancer mortality, it is not very accurate and has led to overdiagnosis and overtreatment," says Dr. Abouassaly, urologist at UH Seidman Cancer Center and Assistant Professor at Case Western Reserve University School of Medicine. "Because prostate cancer can be slow-growing, we recommend active surveillance, a treatment approach during which patients are monitored and tested at regular intervals."
Prostate cancer is the most common malignancy diagnosed in men in the United States. Widespread use of PSA screening led to a decrease in mortality from the disease; however, the screening may have led to overtreatment of clinically insignificant cancers. Although PSA has been validated as a prostate cancer marker, the screening test's accuracy is limited. It is not specific for prostate cancer and cannot discriminate between low-grade versus high-grade disease.
Citing evidence that the risks of screening outweighed the benefits, the U.S. Preventive Services Task Force (USPSTF) released a controversial statement in 2012 recommending against its use. This was met with concern from professional organizations, including the American Urologic Association and Society or Urologic Oncology. The groups warned that this was a disservice to men that would result in failure to prevent avoidable deaths.
In this new review article, the authors found that since the release of the USPSTF statement, the use of PSA for prostate cancer screening has dramatically reduced. They highlighted that while complete abandonment of PSA screening will eliminate all cases of overdiagnosis, it will also fail to prevent 100% of avoidable cancer deaths.
The review of current data found that active surveillance can reduce overtreatment by almost 50 percent at 15 years and that men on active surveillance are not at immediate risk of death from the disease if therapy is deferred until the cancer progresses.
The authors conclude: "Currently, active surveillance is a feasible strategy to reduce overtreatment without compromising the therapeutic window and chance for cure. Future efforts should emphasize strategies to distinguish between clinically insignificant and aggressive prostate cancers so that definitive therapy can be disseminated appropriately."