One line in particular from Sen. Angus King’s announcement that he’ll undergo prostate cancer surgery caught my attention.
In a statement, his office said the senator has experienced no symptoms of the disease, “but a routine medical exam in April revealed some abnormalities in his bloodwork indicating possible prostate cancer.”
While the announcement doesn’t specify which blood test turned up abnormal results, it’s a safe bet that King underwent a common screening for prostate cancer called a “prostate-specific antigen” test. As the Mayo Clinic explains, it detects a protein produced by both malignant and benign prostate tissue. Cancerous cells typically release more of it, so high levels of PSA in the blood can indicate cancer.
Or not, which is why the PSA test has sparked considerable debate in the medical community. Until recently, yearly PSA screening was encouraged for men starting at age 50. But many medical societies now recommend against routine screening for all men, contending it leads to unfounded fears and over treatment.
How the PSA test works
The test itself carries little risk, involving a routine needle stick for a blood draw. But how doctors and patients evaluate the results and use them to decide which treatment to pursue is the tricky part.
Some prostate cancers produce little PSA, so a normal test doesn’t rule out cancer.
At the same time, elevated PSA levels don’t necessarily indicate cancer, sometimes flagging less serious conditions like an infection or enlarged prostate. Only about one in four men with a positive PSA test is ultimately diagnosed with prostate cancer, according to Mayo.
The PSA test also can’t distinguish between aggressive cancers and slow-growing, small tumors that would cause few problems for the patient if left untreated. That leaves oncologists and their patients to decide how to respond to a positive test. Among the options are to do nothing and repeat the test later — called “active surveillance” or “watchful waiting” — or get a biopsy and pursue treatment, such as surgery and radiation therapy. Those more aggressive options can carry serious side effects, including incontinence or sexual dysfunction, according to the National Cancer Institute.
How is catching cancer early anything but good?
For many men, those risks of over treatment pose more harm than an untreated, slow-growing tumor, many experts say. According to one study, about half of men diagnosed with prostate cancer as a result of a PSA test would go on to experience no symptoms without treatment.
Many patients find it hard to do nothing after learning that high levels of PSA are circulating in their blood.
For some patients, the PSA test can be a life saver, particularly for men at higher risk, including those with a family history of prostate cancer.
For others, an abnormal test can cause avoidable stress and anxiety, not to mention costly and unnecessary follow-up tests and treatment, some experts say.
The Maine Coalition to Fight Prostate Cancer stresses the importance of early detection, but also expresses concerns about over treatment on its website.
“While 25% to 30% of men diagnosed with prostate cancer do die from this disease, nearly 90% of men are electing to do a treatment. MCFPC would like to see treatments reduced by 50% to minimize irrevocable incontinence and impotence that can result from current primary procedures,” the group says.
In recommending against PSA testing, several medical groups raise an important point, one that’s gaining traction in the health care world even beyond prostate cancer screening:
Detecting a disease early does not necessarily lead to a better outcome.
In other words, knowing early that you have prostate cancer may not mean you’re less likely to die from it.
In general, early-stage cancers are easier to treat than more advanced cancers. But small abnormalities revealed by screening don’t always point to a need for treatment.
The U.S. Preventive Services Task Force, an independent panel that reviews evidence to help doctors evaluate preventive screenings, recommends against PSA-based screening, regardless of a man’s age. Much of their reasoning boils down to concerns about over diagnosis and gaps in the research.
The group found “moderate certainty that the benefits of PSA-based screening for prostate cancer do not outweigh the harms” posed by treatment. The screening offers a “very low probability of preventing a death from prostate cancer in the long term,” the task force states.
The American Cancer Society also does not recommend that all men get tested for prostate cancer, detailing its thinking in the publication “Should I be tested for prostate cancer?”
The U.S. CDC recommends against PSA-based screening for men with no symptoms, but other groups recommend patients talk with their doctors at certain ages or get screened based on life expectancy and family history. Most agree that men should be informed about the potential harms and benefits before undergoing screening.
Mayo outlines the varying guidelines in a helpful chart here.
In the wake of all this debate, researchers are investigating ways to improve the PSA test.
We don’t know how King, already a skin cancer survivor, arrived at the decision to undergo surgery. (Some research suggests a link between prostate cancer and melanoma.) But King expressed confidence in his choice and in his doctors.
“We have a plan to treat it, and plan for a full recovery,” he said in the announcement.