Late Thursday afternoon, we learned that the United States Preventive Services Task Force (USPSTF) was going to recommend against routine prostate cancer screening by PSA test.
The USPSTF is a panel of primary care physicians charged with the task of compiling evidence-based preventative medicine guidelines.
Two years ago, the USPSTF was attacked when they recommended against mammograms for women 40-49 years old. The panel argued that too many women were being subjected to unnecessary biopsies to justify the patients whose lives were saved by the mammography. Many criticized the decision, saying it was akin to health care rationing.
Similarly these new recommendations for prostate cancer reflect a growing concern that PSA screening is resulting in unnecessary treatment without impacting overall survival.
The evidence supporting prostate cancer screening is not without controversy. A large American trial failed to illustrate a significant difference in prostate cancer specific deaths between the screening and control groups. However, the data was premature without sufficient follow-up to appreciate a screening benefit.
Additionally, a majority of the patients in the control group were screened during the study period, possibly obscuring the results of the trial. A study of over 200,000 men in Europe, which followed patients for a longer period of time than in the American trial, found favorable results; 9 years following initiation of PSA screening, the study group experienced a 20% decrease in prostate cancer specific deaths, when compared to patients who were not screened. In Sweden, a trial followed men for 14 years, finding that routine PSA screening resulted in a 50% reduction in prostate cancer related deaths.
The most powerful argument in favor of PSA screening, however, is the reduction in prostate cancer mortality we have witnessed since PSA screening first became available; a 39% reduction between 1990 and 2007. Prostate cancer mortality is now the lowest it has been since the 1930’s when life expectancy was much lower.
PSA is not a perfect test. Prostate cancer can be an indolent cancer, taking many years to decades before it causes problems or it can behave in a highly aggressive manner. PSA is not able to differentiate these two cases. However, by tracking PSA velocity and density we can more accurately predict ones risk of cancer.
Furthermore, young men worry about the side-effect of prostate cancer treatment, loss of continence and potency, particularly given the long natural history of prostate cancer. Thus many young men are forgoing screening with only 24% of men 50-54 getting screened.
Ironically, younger patients are the ones who benefit most from routine screening. At a younger age, the cancer detected is still localized and therefore more easily treated.
In the hands of experienced clinicians at high-volume cancer centers the risks of side effects are reduced.
At our institution, use of the SMART (Samadi Modified Assisted Robotic Technique) surgery technique has allowed us to achieve 97% continence and 81% potency rates at 1 year following surgery.
Recently published papers have also demonstrated that younger age at the time of treatment is a predictor for retained continence and potency.
The recommendations imply that blissful ignorance regarding one's cancer status might be the best course in order to avoid the anxieties related to a cancer diagnosis.
Prostate cancer, however, has no true signs or symptoms. Although it can present with frequency or urgency, these symptoms are associated with more advanced disease and are more often caused by benign conditions.
Additional signs of the disease, bone pain for instance, result from metastases. Thus without PSA we would be waiting for patients to present with advanced and often incurable cancer.
Friday, I met with many men upset by the USPTSF announcement. They find security in knowing that their cancer was not only treated but diagnosed, and they are saddened by the fact that this opportunity might not be available for so many other men.
We simply cannot forget that 30,000 men die every year from prostate cancer. It is not a benign condition and can just be ignored; we need to continue to fight this illness. The PSA test is the only tool currently available and while researchers are working tirelessly to develop a more sensitive test we would be remiss to stop screening.
Bottom line: perfection should not be the enemy of good.