Why Doctors Are Rethinking Needless Prostate Biopsies
"Recently, I saw a man who was sent in [because of] an elevated PSA [prostate-specific antigen]," said Kevin T. McVary, M.D., director of the Center for Male Health and a professor of urology at the Stritch School of Medicine at Loyola University Medical Center in Illinois. "And he had, I would call it, a semi-recognized urinary tract infection, which is a known false positive [for prostate cancer diagnosis]. It flares the prostate and PSA can skyrocket. I say 'semi' because it was there; the referring doctor just didn't really drill down into the dirt very far."
Prostate-specific antigen (PSA) is a protein made by both normal and cancerous cells in the prostate gland. It has been used as a metric for determining prostate health and cancer risk since the 1980s. But, as the anecdote from McVary shows, evaluating the results and/or efficacy of blood and other tests often requires an entire team. In an ideal world, that team includes equal participation from the patient, the doctor and possibly additional specialists from various medical fields.
Screening for PSAs
At first, PSA fluctuations were tracked in conjunction with the progression of cancer in existing prostate cancer patients. Later, doctors began screening for cancer and evaluating prostate cancer aggression by measuring the quantity of PSA proteins in blood and prostate tissue, the latter being collected via biopsy.
Until fairly recently, doctors typically recommended that men receive a prostate biopsy around the age of 50 and have bloodwork done at least every year afterward. This practice, as a standardized procedure, has become more dependent on a nuanced discussion and an informed dialogue between doctor and patient.
"We know that biopsies have been too ubiquitous in the past and so now we're trying to dial back as we become a little bit more sensitive to ideas about risk," McVary said.
He emphasized that patients should consider a wide variety of factors when evaluating cancer risk, as well as screening and treatment options.
"Don't be a reflex, be a reflector," said McVary, who is an author and associate editor of the Journal of Urology. "Reflect on it; you just want to understand your urologist's thinking."
DREs and MRIs
Doctors have been measuring PSA levels in blood samples as a method of screening for cancer risk for more than 30 years. When blood tests revealed high PSA levels, a biopsy was often the go-to option for follow-up and further evaluation of cancer risk. Now, it's all about developing a fuller picture of the prostate and its condition.
Digital rectal exams (DREs) are still one of the first screening methods many men will encounter. Yep, your doctor is going to insert a gloved finger into your rectum and feel for any hardened or otherwise abnormal lumps or formations that may indicate the presence of cancerous tissue. It's still effective and mostly painless.
Given modern tools, however, doctors are less likely to rely on a DRE as the sole determinant of prostate health, in which case, ultrasound technology is useful. A transrectal ultrasound (TRUS) involves the insertion of a lubricated probe into the rectum and the probe releases soundwaves to form an image of the prostate, which is just in front of the rectum.
While safe, all forms of penetrative screening come with the risk of varying degrees of discomfort and slight pain during and after the procedures. So, what's the alternative?
McVary expressed some level of excitement about blood and urine tests as well as prospects regarding MRI (magnetic resonance imaging) technology in evaluating cancer risk in patients.
"There are other blood tests where you can estimate the risk of cancer much better than just the PSA alone," he said. "Another one is the prostate health index, which is an assortment of proteins in the blood. And I particularly still depend on PSA change. What is the PSA velocity? Those types of, I would call them more nuances of PSA and PSA-like molecules, can really support your decision [to biopsy] or maybe we should reassess."
While safe, all forms of penetrative screening come with the risk of varying degrees of discomfort and slight pain during and after the procedures.
If the results of a DRE or a PSA blood test reveal cause for concern, a doctor may request a urine sample to further evaluate for the presence of certain gene elements that are usually only found in men with prostate cancer. Additionally, PSAs are actually divided into two categories, and PSA tests designed to look for one of them can help clarify prostate cancer risk for doctors and their patients.
The two types of PSA are called bound PSAs and free PSAs. As the names imply, bound PSAs are bound to a protein and free PSAs are not. If a general PSA test reveals a high quantity of overall PSAs, a doctor may look closer to determine the ratio of bound PSAs to free PSAs, because prostate cancer tends to correlate with lower levels of free PSAs than the quantity found in cancer-free patients.
McVary also expressed enthusiasm about the usefulness of MRI as a cancer-risk evaluation tool.
"It has to be done in the right way, processed in the right way and usually in concert with a team approach," he said, "a radiologist and a urologist working in a program together."
When these team members are not working directly in conjunction with one another, too many discrepancies can arise, according to McVary. Handling basic details, such as the transfer and translation of digital images and data from the radiologist to the urologist, can become problematic. But as these technical and pragmatic issues become sorted out through regular adoption of MRI technology for prostate cancer risk evaluation, MRI may become a very useful tool for doctors and patients working together against the development and/or progression of prostate cancer—and toward the avoidance of a biopsy.
Take, for example, an octogenarian patient. With an 80-year-old patient, a number of noncancerous conditions might cause PSA numbers to reflect those seen in cancer patients. The MRI offers a less invasive alternative to a biopsy and can look at factors other than PSA levels. The possibility of overtreatment, however, remains an issue worth considering.
"[MRI is] a very promising technology in development, maybe needing refinements and more access," McVary said. "It's improving but not perfect. Also, to the elderly patient, I would say, 'This is just a PSA in a different type of clothing, sir.' Because that can still send us down a pathway of overtreatment."
Ultimately, it's up to you
The big emphasis when it comes to prostate cancer screening and the steps that may precede or provide alternatives to prostate biopsies is to talk to your doctor about your options. This boils down to, as McVary calls it, "shared decision-making." He points out that patients and their doctors need to evaluate factors such as age and related medical history when considering screening and/or treatment options.
Again, the example of the elderly patient provides a good context for understanding this process.
"Before you would do a PSA on an 80-year-old, you would say, 'What are we going to do about this if the PSA is not absolutely normal? You're 80 years old, and this could lead us down a pathway of establishing prostate cancer and, if we found such a cancer, would we do anything about it?'" McVary said. "And that's a question that I feel I have daily with patients."
The process described by McVary requires participation by both patient and medical provider. Only your doctor can make qualified recommendations when it comes to how you should screen for prostate cancer or any other medical condition. While the recommendation comes from the doctor, the decision ought to come from the patient. The medical team is not there to demand a path of treatment, but to inform the patient of every option available and to encourage the patient to take the action they feel is right for them.
Or, as McVary put it, "My mentor once said to me, 'Just because you know a fact doesn't mean you have to act on it.'"