Former president Joe Biden’s announcement that he had an aggressive form of prostate cancer may have surprised many people, but not prostate cancer specialists.
True. At age 82, Biden is 15 years older than the average man who is diagnosed with the second-most common cancer in men. (Skin cancer tops the list.)
It’s also true that having served as president and vice president for 16 years, Biden benefited from top-drawer medical care.
But testing for prostate cancer can be fraught, particularly among men older than age 70, and sometimes it can go from undetectable to metastatic — spreading to bone, as in Biden’s case, or to lymph nodes — in a matter of months.
“Something like President Biden’s presentation is a little surprising. However, for somewhere around 5% of men, when they start their workup for prostate cancer, we find that they’re already metastatic. It’s called a de-novo metastatic presentation,” said Dr. David Strauss, University of Colorado School of Medicine urologic oncologist who sees patients at the UCHealth Tony Grampsas Urologic Cancer Care Clinic – Anschutz Medical Campus.
The PSA test: critical in spotting prostate cancers early, but imperfect
With the other 95% of cases, prostate cancer’s progression is more predictable — if also a challenge to accurately detect. That’s because the prostate-specific antigen (PSA) test can be sensitive to a fault.
The PSA test, the primary screen for prostate cancer and a vital tool in detecting prostate cancer early, spots proteins in the bloodstream that prostate cancer creates. But its false-positive rate is close to 50%, and it’s even higher among men ages 70 and older. In addition to the psychological burdens that a high PSA score introduces, false positives can lead to needless, painful biopsies and also overtreatment that can cause incontinence, erectile dysfunction and other issues for a cancer that usually grows so slowly that most who have it will die of other causes. In fact, around 80% of men of Biden’s age have a slow-growing disease.
In addition to PSA screening, MRI scans can now detect dangerous prostate cancers, vastly improving the accuracy of biopsies and enabling treatment before they have spread.
Understanding the varying PSA testing guidelines
Medical organizations universally recommend PSA screening, although with slightly different guidelines.
The U.S. Preventative Services Task Force (USPSTF) recommends PSA screening for men 55-69 after discussion of potential benefits and harms of screening with a clinician, but explicitly recommends against prostate cancer screening in men ages 70 and older. (The USPSTF is in the process of updating those guidelines, which were last published in 2018.)
The American Cancer Society recommends that men of average risk have a PSA test at age 50, and that, “Because prostate cancer often grows slowly, men without symptoms of prostate cancer who have less than a 10-year life expectancy should not be offered prostate cancer screening, because they aren’t likely to benefit from it.”
Men at high risk — Black men or those with a first-degree relative (father or brother) diagnosed with prostate cancer younger than age 65 — should get a PSA test at age 45. Those at very high risk, which include more than one first-degree relative with early age prostate cancer, should get a PSA test at 40.
The American Urological Association recommends prostate cancer screenings starting at ages 45 to 50 and then advises men ages 50 to 69 to be tested every two to four years. Men at higher risk — including those with Black ancestry, men with certain genetic mutations and those with a “strong family history of prostate cancer” — should be screened starting from ages 40 to 45.
Consistent across the board is that, by age 70, these experts recommend PSA testing only in select patients who exhibit a substantial life expectancy. But that’s a rule that’s often broken, and for good reasons.
PSA scores over time can hold clues as to long-term prostate cancer risk
Strauss says the trend in a patient’s PSA score is one reason for ignoring the over-70 guideline. If a 70-year-old’s PSA scores have been consistent since his mid-50s, it probably makes sense to stop testing, as the risk of detecting high-risk cancer may be low. But in cases where PSA is rising over time, Strauss may continue to order PSA tests into a patient’s late 70s, he says, on a case-by-case basis.
In cases where PSA tests and subsequent biopsies detect fast-growing prostate cancer that’s still confined to the prostate itself, treatments can vary with age and medical condition. While prostatectomy can be an option for men in their 70s, radiation therapy is typically the first choice, Strauss says.
For those such as Biden, for whom the disease has spread, the standard of care has been hormone therapy combined with chemotherapy. But the arsenal of treatments is expanding, Strauss says.
Understanding treatment options for prostate cancer
“Over the last five to 10 years, there’s been an explosion of medicines and other approaches to offer patients with metastatic disease,” he said.
For example, the standard metastatic prostate cancer treatment of androgen deprivation therapy (ADT) now typically involves two different types of ADT — doublet therapy — or triplet therapy, which adds chemotherapy to doublet therapy, Strauss says.
Other new treatments include olaparib (Lynparza) and rucaparib (Rubraca), recently approved by the U.S. Food and Drug Administration, to help men with BRCA-positive metastatic prostate cancer. These treatments are based on new research that hons in on the genetic aspects of metastatic prostate cancer. Whereas hormone therapy aims to deprive cancer cells of the testosterone they use to grow and spread, these drugs impair the cancer cells’ ability to fix their DNA. Whether Biden’s prostate cancer exhibits BRCA mutations — best known for their role in breast cancer — has not been disclosed.
Radiation therapy or surgery targeting the prostate has not been the standard of care for men with metastatic prostate cancer, Strauss says. But that may change depending on the results from two U.S. clinical trials that are testing whether radiation or surgery improves those patients’ outcomes despite their metastatic disease. University of Colorado School of Medicine researchers have many trials open in the metastatic prostate cancer space at UCHealth University of Colorado Hospital on the Anschutz Medical Campus, Strauss adds, ranging from surgery and radiation to new systemic therapies.