Prostate cancer screening guidelines have been evolving for more than a decade, but new research suggests that recommendations against routine prostate cancer testing may have come at a steep price -- more men getting diagnosed with advanced prostate cancers.
The study found that rates of advanced prostate cancers rose by about 5% per year through 2016.
There was some good news, though. After routine use of the prostate specific antigen (PSA) test was no longer recommended for the majority of men, rates of early prostate cancer went down by 6.9% per year in men between 50 and 74 years old. (Early prostate cancers may be very slow-growing and may not need treatment.)
"Men have to talk with their providers. They have to make sure they understand all of the benefits and harms of PSA testing. The benefits are that they may avoid advanced disease and may extend their life expectancy," said senior study author Dr. Ahmedin Jemal, scientific vice president of surveillance and health services research for the American Cancer Society.
But there are also potential harms from getting a PSA screening. Some are from treatment, but there are also harms from the need for further testing after a PSA test shows possible cancer. After a suspicious test result, a doctor may suggest a biopsy. That's a procedure to remove a small sample of tissue from the prostate.
"Biopsies can lead to bleeding or infection. And, 1 in 100 biopsies lead to hospitalizations," Jemal said.
The problem is that prostate cancer screening isn't clear-cut. The PSA test can be helpful, but not always. The PSA measures prostate-specific antigen -- that's a substance made by cells in the prostate gland. It can be made in normal and cancer cells, according to the American Cancer Society.
The higher the PSA level, the more likely it is that a man has prostate cancer. But there's no set point where a man can be sure he has cancer (or doesn't). So an unusual PSA finding may lead to additional testing.
Because of these uncertainties, the U.S. Preventive Services Task Force recommended against PSA screening for men 75 and older in 2008. In 2012, the USPSTF expanded that recommendation to include men of all ages. At the time, the task force concluded that any potential benefits from screening wouldn't be greater than possible harms from tests like the PSA.
In 2018, however, the task force reviewed newer research and revised its recommendations. It still recommends that men aged 70 and older forgo PSA screening. For men 55 to 69 years old, the task force says the decision to screen or not should be an individual one. Patients and their doctors should consider a number of factors, including family history of certain cancers, other chronic medical conditions, and race or ethnicity.
Jemal noted that the new study didn't include changes in PSA screening rates that may have occurred after the task force's most recent recommendations.
The study included data from 2005 to 2016. During that time frame, more than 2.2 million American men were diagnosed with prostate cancer. Most -- 87% -- had early-stage prostate cancer. Only 5% had prostate cancer that had spread to areas far from the prostate.
Past-year routine PSA testing rates among men aged 50 and over declined from about 41% in 2008 to around 38% in 2010, to 31.5% in 2013, and remained unchanged in 2015, according to self-reported information.
"Now the problem is: Does the harm avoided by not PSA-testing outweigh the harm associated with the morbidity and mortality [sickness and death] of distant prostate cancer? It's a tough call," said Jemal. He said he hopes there will be advances in diagnostic tests for prostate cancer in the future.
Dr. Edmund Folefac, a genitourinary medical oncologist with the Ohio State University Comprehensive Cancer Center, reviewed the findings and said they were expected by those who treat prostate cancer.
"It's important that we don't make perfect the enemy of good. The PSA test has flaws, but when used appropriately, it can diagnose cancers early," Folefac said.
He added that the odds of surviving five years after an early prostate cancer diagnosis are nearly 100%. But if the cancer has spread to other parts of the body, the five-year survival rate drops dramatically.
Folefac said if he were writing the guidelines, he would recommend that every man who is high-risk should be screened. That includes black men (they have a much higher incidence of disease) and people with a family history of certain cancers (prostate, colon, breast, ovarian, cervical), he said.
And, Folefac thinks that doctors should tell patients whether or not they need to be screened. "The onus should be on the doctor, not on the patient. When you say it's an individual decision, the onus is on the patient, and you are asking the patient to gather information from all kinds of places that may or may not be helpful at all," he explained.
Folefac also took exception to the task force's recommendation for no testing of men 70 and older. He noted that some people are quite healthy at 70 and have a long life expectancy. In such a case, testing might make sense.
"There shouldn't be a one-size-fits-all cutoff for age," he said.
The study was published May 20 in the Journal of the National Cancer Institute.
Learn more about prostate cancer screening from the American Cancer Society.