"My GP Just Doesn't Believe in PSA"
“My GP just doesn’t believe in PSA”, a new patient told me today. He was referred to me with an elevated PSA drawn elsewhere and some subtle changes on rectal exam. Unfortunately I am starting to hear this exact refrain with greater frequency. When the US Preventative Services Task Force made PSA recommendations in 2012 the concern was that we would start to see a reduction in prostate cancer detection and ultimately see men present in the more advanced stages of the disease. At first, my own clinical experience post 2012 did not follow this. The elevated PSA consult remained a common office consult and using a multivariate approach to risk assessment I would try my best to navigate these men through their clinical decision-making. That was of course until the Canadian Task Force on Preventative Healthcare published its own recommendations in October, primarily using data based on the flawed US recommendations.
In the few short months since that time I have had numerous conversations at an individual level with many of my primary care colleagues to try and explain how prostate cancer detection is a nuanced clinical endeavor. Still, the adoption of PSA ‘non-belief’ has grown. The busy GP is far too busy to fully understand the very real differences between population wide screening and clinical detection at an individual level. Yes there is a wide gap between indolent disease and advanced disease but it requires an individual approach that takes into account known risk factors and patient desires. Certainly the idea of not doing a PSA needs to be completely discouraged. The concept of not “believing” in PSA I find entirely absurd.
The litmus test of any screening tool is that it needs to detect disease early, be cost effective and have a treatment available that alters the natural history of the disease. PSA by itself is not a great screening test. With respect to prostate cancer the challenge is that many men will not require treatment. There are clearly consequences to having a biopsy as well as potential harm created by changes in urinary and sexual function. The two task force recommendations weigh these factors heavily and discard the notion that a diagnosis of prostate cancer does not always follow a direct path to treatment. With careful follow up and the use of newer technology such as MRI we can better stratify an individual’s cancer risk. Active surveillance for low risk disease has become widely adopted, especially here in Canada.
Let us be very clear that prostate cancer is a real disease. While up to 1 and 6 men might be diagnosed with prostate cancer in their lifetime and only 20% of these men might in fact have clinically consequential disease I would submit that still is a large number of men. As I have written many times before on this site and elsewhere, while we have some knowledge about clear risk factors such as family history and ethnicity, in my experience the large majority of men that have presented with meaningful disease have had no clear or prior risk factor. Until we get a better tool that is widely available, PSA is the best thing that we have. Certainly prostate cancer detection in a world without PSA earns a trip back to the 1970s. Understanding how to interpret it and not submit it to a one size fits all approach is what needs to be taught better. The concept of doing a baseline PSA is very important. There is no way that anybody can interpret a PSA in isolation without having a sense of where it might have been 3, 5 even 10 years ago as well as having an understanding of how the prostate feels and how large it may be. Adding to this an understanding of risk factors and patient preferences allows for a better decision-making process around biopsy. We can’t simply abandon an entire generation of men waiting for something better to come along. Those men that are destined to be harmed by prostate cancer must be found and offered a chance at cure.
I would call upon my fellow urologists and radiation oncologists to reach out to their local communities and speak to colleagues at a primary care level. Our understanding of prostate cancer detection is clearly imperfect but we have made strides in reducing prostate cancer mortality and if we completely abandon the one important test that we have come to rely on over the last 25 years we will court disaster. Like the current travesty with the antivaccine debate it is not good enough to simply say “I don't believe” in something when data clearly suggests otherwise. Yes, PSA is imperfect and the waters are a little muddy but understand what you are dismissing with the potential downstream harm to many men before you commit to that belief. Support the thoughtful clinical use of PSA and not abandon it wholesale. Let urologists at least have the chance to assess these men and stratify their risk
Rajiv Singal
Twitter: @DrRKSingal