This morning, actor Ben Stiller revealed that he had been diagnosed with prostate cancer two years ago, at the age of 48. He shared the news on The Howard Stern Show and published a detailed firsthand account of his experience on Medium.
A routine prostate-specific antigen (PSA) test determined he had the cancer, which doctors detected early and were able to treat successfully, he says.
Three months later, his doctors told him he was cancer-free - and he credits the PSA test with saving his life.
With happy-ending stories like that, it’s not hard to understand why the PSA was once recommended annually for men over 50.
Prostate cancer is the most common cancer affecting men in the United States besides skin cancer. Nearly 99 per cent of men diagnosed with it survive at least 5 years, according to National Cancer Institute data.
But recently, the screening test has fallen out of favour. In fact, in 2012, an advisory panel completely recommended against it as a tool for preventive care.
Still, the debate rages on: Many health experts - especially urologists - disagree strongly with that new assessment.
So what does this mean for you and your prostate? Read on to learn more about the blood test—and if you should actually roll up your sleeves for one.
What Is Prostate-Specific Antigen (PSA)?
The cells in your prostate naturally produce a protein called prostate-specific antigen.
Small amounts of it - usually defined as below 4 nanograms per millilitre of blood (ng/mL) - are considered normal. (In fact, the average levels for healthy guys in their 40s can be below 1 ng/mL.)
But higher levels can indicate that something’s not quite right with your prostate.
Case in point: men with prostate cancer often have elevated PSA levels.
In fact, the U.S. Food and Drug Administration (FDA) initially approved the PSA blood test back in 1986 to monitor the progression of the cancer in men who had already been diagnosed with it.
So What’s Wrong With the PSA Test?
For one thing, it’s not a very specific test, says Dr Otis Brawley, chief medical officer for the American Cancer Society.
Cancer isn’t the only thing that can raise your PSA levels.
Conditions like prostatitis, an inflammation of the prostate, or benign prostatic hyperplasia - an enlarged prostate - can also cause your PSA levels to spike. Even recent sex can temporarily increase them, too.
So preventively testing PSA levels often incorrectly identifies men who don’t have cancer.
One reason? Unlike, say, a pregnancy test with a plus sign, PSA tests aren’t clearly positive or negative, says Dr Stacy Loeb, assistant professor of urology and population health at NYU Langone Medical Centre.
That’s because the “normal” 4-ng/mL cutoff isn’t foolproof, she says.
If your levels are between 4 and 10 ng/mL, you have about a one in four chance of having prostate cancer, according to the American Cancer Society (ACS).
Higher than 10, and you’re looking at a 50-50 situation.
Steve Silberberg, 55, came out on the more fortunate side of these equations.
Four years ago, Silberberg scored a PSA reading of 8 - almost twice as high as the “normal” cutoff.
He went on for further testing, and his prostate biopsy came back normal. But this year, his PSA levels climbed above 10, so he went through a second biopsy.
This one was normal, too: Despite his sky-high PSA reading, his prostate was actually just fine. Silberberg’s doctor simply suspects he may just have a large prostate that’s growing as he ages, raising his PSA levels.
Silberberg’s experience shows that PSA testing is not very specific. But unfortunately it’s not very sensitive, either.
That means it also misses a good chunk of men with normal-range PSA levels who do have prostate cancer.
In fact, about 15 per cent of men with a PSA below 4 ng/mL actually have the cancer, according to the ACS.
PSA levels don’t need to be off the charts to indicate that a cancer is developing.
In fact, when Gary Perkins, 64, had a PSA test back in 2014, it came back just above 4 ng/mL - definitely not high enough on its own to warrant any alarm bells.
But his family doctor noticed Perkins’s levels had actually been slowly increasing over the last decade or so. So he sent him to a urologist for further evaluation.
A prostate biopsy confirmed cancer: He underwent targeted radiation therapy and is cancer-free today.
That’s because as prostate cancer becomes more advanced, PSA levels generally rise.
PSA Tests Aren’t Enough - So What’s the Next Step?
As Perkins’s case shows, PSA tests aren’t conclusive. So doctors must monitor changing PSA levels and do further tests on men with higher levels to confirm a prostate cancer diagnosis.
The latter is where the prostate biopsy comes in.
In this procedure, a doctor uses a thin, hollow needle - usually inserted through your rectum - to remove a sample of cells from your prostate. The area is numbed by an injection to reduce discomfort.
Then, he or she will examine the cells under a microscope to check for signs of cancer.
The Problem With Prostate Biopsies
Besides being a literal pain in the butt, this procedure also comes with a pretty substantial risk of side effects, Dr. Loeb says.
And the chances of experiencing at least one is hefty: Within 35 days of a prostate biopsy, 44 per cent of men reported pain, two-thirds said they had blood in their urine, and more than 90 per cent noticed blood in their semen, one studying the journal BMJ found.
Perkins says his biopsy wasn’t that bad.
But Silberberg called his “the most painful medical procedure I’ve ever had.” After his most recent biopsy, he peed blood for two weeks.
In fact, in the study, one in 10 men sought treatment from their primary care doctors for issues that stemmed from their biopsy. One percent was even hospitalized as a result of it.
That’s what happened to Shane Greenstein, 56, a Harvard Business School professor who developed a life-threatening case of sepsis - a serious infection complication that can lead to organ failure - after a prostate biopsy in 2010.
He beat the infection—and learned he didn’t have cancer, either.
With the frequency of side effects, it’s not really surprising that 1 in 5 men said they’d hesitate to get another biopsy, the study found.
“This is obviously an invasive procedure with potential risks including bleeding and infection,” Dr. Loeb says. “Even once the prostate cancer is diagnosed, not all prostate cancers are actually harmful or would cause the man any problems during his remaining life.”
And that’s the other big problem: Even though a biopsy can show cancer, it can’t always tell how aggressive a case it is, Dr. Brawley says.
In fact, between 23 and 42 per cent of all cancers detected by PSA tests in men without symptoms would have never caused them any health problems, a study from the Netherlands suggests.
As a result, you might get cancer treatments like surgery or radiation - which have their own side effects, including incontinence or bowel problems, erectile dysfunction, and even death - for a disease that never would have killed you or even caused you any ill effects, Dr. Loeb says.
But Does PSA Screening Save Lives?
PSA tests - and the subsequent additional tests they require - aren’t perfect. But are they actually saving lives?
Unfortunately, the answer to this isn’t clear: Randomised controlled trials - medicine’s gold standard, in which some men were randomly assigned to either undergo screening or not - have been inconclusive.
The U.S. Preventive Services Task Force, an independent panel of national experts that advises Congress, looked mainly at two large trials before releasing its most recent guidelines against preventive screening, which were finalized in 2012.
One—the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial—found that while screening increased the rates of prostate cancer diagnoses by 22 percent, it didn’t actually end up saving any lives over the 7 to 10 year follow up.
That’s likely because of all the reasons the test isn’t perfect: It picks up some cancers that wouldn’t have posed a problem, identifies some men who don’t have cancer at all, and can lead to diagnostic procedures and treatments that pose their own risks.
The other - the European Randomised Study of Screening for Prostate Cancer - showed screening reduced the risk of death from prostate cancer by about 27 percent after 13 years of follow-up.
But these benefits came at a price: A total of 27 additional men would need to be diagnosed with prostate cancer to save one life.
That means the other 26 men would be told they have cancer—and potentially treated for it, with all the risks that entails—even though the disease never would have killed them.
After the Task Force analysed the numbers from both trials, they didn’t believe the benefits outweighed the harms. As a result, they recommended that men shouldn’t be screened.
Meanwhile, other organisations - looking at the exact same data - backed away from a blanket recommendation and decided men should draw their own conclusions instead.
The American Cancer Society, American Urological Association, and American College of Physicians all recommend men should be screened only after a discussion with their doctors.
What Does This Mean For Prostate Cancer Down the Line?
In the year after the Task Force issued a draft of their screening recommendations, rates of prostate cancer diagnoses in men over 50 declined by 16 per cent, according to a study in JAMA.
And the decline continued: Over the course of the next year, prostate cancer rates in men ages 50 to 74 fell another 6 percent, a just-released follow up study found.
But when looking specifically at later-stage, advanced prostate cancer - the more worrisome kind - the diagnoses rates didn’t change at all.
That suggests that screening may have mostly been picking up the prostate cancers that wouldn’t have caused any serious health problems.
Still, it’s too early to determine what effects moving away from universal screening may have on prostate cancer mortality, says Dr. Loeb.
However, a 2014 study in the journal Cancer used a mathematical model to estimate that if all screening came to a halt, twice as many men would develop metastatic prostate cancer - the most advanced and deadly kind - by 2025.
So instead of stopping screenings completely, doctors should strive to target both PSA testing and the steps that follow to people who could actually benefit from it, Dr. Loeb says.
Fortunately, new and more sophisticated types of PSA testing - some already in use - might help distinguish cancer from other causes of high PSA levels. They might also aid in separating cancers that need treatment from those that don’t.
“Men should be informed about the availability of a screening test and told about the benefits and the harms so that they can choose for themselves,” says Dr. Loeb. “I don’t think it’s appropriate for us to make that decision for them.”
So Should You Get Your PSA Tested?
There’s no single answer to who should get screened, but experts do have a few recommendations to help you make the best-informed decision for your specific situation.
1. In your 40s
Start talking with your primary care doctor about the benefits and risks of regular screening if you have a family history of prostate cancer or are African American. Both of these factors can raise your risk of developing prostate cancer, and doing so at an earlier age.
Otherwise, ask about a baseline screening, Dr. Loeb recommends.
A new study in the Journal of Clinical Oncology found 82 per cent of men who died of prostate cancer had a PSA level above the average—0.68 ng/mL—when tested between ages 40 to 49.
Focusing regular screenings on men with a baseline higher than average for their age group—instead of doing PSA tests on everyone—might catch more cases of life-threatening cancer while reducing unnecessary biopsies and treatments, says Dr. Loeb.
2. In your 50s
Even if you don’t have a family history or a high baseline, it’s time to begin discussing regular screenings.
The biggest benefits for PSA tests occur in men 55 to 69, according to the American Urological Association. In large part, that’s because it’s the age when your risk of developing prostate cancer is highest.
You can reduce the risks and preserve most of the upside by getting screened every two to four years instead of every year, the organisation notes.
3. At age 70
Talk with your doctor about whether you still need screenings.
For all but the healthiest men, the risks of screening likely outweigh the benefits at this age. Since most cases grow slowly, you’re more likely to die of something other than prostate cancer, says Dr. Loeb.
4. If you have symptoms
Early prostate cancer has no warning signs.
Symptoms of advanced prostate cancer include pain in the bones of your back, hips, or pelvis; trouble peeing; blood in your urine or semen; and shortness of breath.
See your doctor if you develop them - the benefits and risks of getting PSA tests change once you have signs of the disease. You’re more likely to actually have cancer if you’re taking the PSA test because of symptoms, rather than just for screening.
Plus, the symptoms could also be signs of other serious health problems that require treatment.
5. If you’re diagnosed with prostate cancer
Screening means finding cancer in people without symptoms, so once you’re diagnosed, the term no longer applies.
But repeated PSA testing at intervals determined by your doctor could be used to monitor your malignancy to make sure it’s not getting worse, says Men’s Health urology advisor Dr Larry Lipschultz, professor of urology at Baylor College of Medicine in Houston.
This treatment method is called active surveillance - meaning closely following your cancer, and starting treatment only if it shows signs of getting worse - and it’s a perfectly acceptable treatment option, he says.
In fact, only about one-third of men who choose active surveillance end up needing radiation or surgery, according to the American Cancer Society.
So watchful waiting may be able to save you from unnecessary and potentially harmful treatments that wouldn’t end up helping anyway, while still keeping your disease from advancing.