Studies examine effectiveness of prostate screening
With two new studies out debating the use of
the PSA test to screen for prostate cancer, the
controversy continues on whether prostate
screenings are leading to over-diagnosis and
aggressive treatment.
Franklin Freidman, MD, a urologist on the Backus Hospital Medical Staff, said many people assume that if cancer is found, then radical surgery is automatic.
“There are so many types of treatments now, and it is important to tailor treatment to patients and their medical conditions,” he said. “This the best test we have right now and it is important for early diagnosis.”
In the United States, death rates from prostate cancer have fallen about 4% since 1992, five years after the introduction of PSA testing.
In March, the New England Journal of Medicine published results from American and European studies that questioned whether screening is effective and whether it does more harm than good.
The ongoing studies cite the high risk of overdiagnosis and overtreatment, but the findings were not definitive. The article stated a shared decision-making approach to PSA screening seems appropriate at this time.
Dennis Slater, MD, a medical oncologist on the Backus Hospital staff, stresses critical procedural differences between the two PSA screening trials.
Because PSA screening is not practiced in Europe, the trial there more accurately reflected no screening in a control group.
“The European trial showed a 20% reduction in prostate cancer mortality at nine years and can be considered a positive trial,” he said. “However, any enthusiasm for prostate screening is dampened by this statistical extrapolation from the European trial: to prevent just one prostate cancer death, 1,410 men needed to be screened, accounting for an additional 34 cancers diagnosed per 1,000 men and 48 additional treatments.”
Dr. Slater said he is certain that screening practice guidelines will change soon.
“The current PSA screening guidelines do not conform to the biology of the disease or heterogeneity of cancer risk among men and cannot be justified with shrinking health care resources,” Dr. Slater said. “At a minimum PSA screening should be performed every four years rather then annually in men at average risk. Perhaps men at higher risk should continue to be screened with PSA and DRE annually, although proof of the cost effectiveness compared to a less intensive program is unknown. Men 75 years or older should not be routinely screened in the absence of any clinical trials suggesting benefit.”
Dr. Freidman said with many options for treatment, such as medication, robotic surgery, cryotherapy, radiation, and seed radiation therapy, doctors will continue to test and then follow with active surveillance or treatment depending on the patient.