Just as the tumultuous debate over breast cancer screening guidelines has begun to fade from the headlines, a new screening issue – this one regarding prostate cancer – has taken its place.
Two new studies published Tuesday in JAMA show that fewer men are being screened for prostate cancer and fewer early stage cases are being caught.
“Both the incidence of early-stage prostate cancer and rates of PSA screening have declined and coincide with the 2012 (U.S. Preventive Services Task Force) recommendation to omit PSA screening from routine primary care for men,” wrote study authors from the American Cancer Society.
In 2012, the federal USPSTF recommended against PSA screening for average-risk men of all ages, saying the benefits of PSA-based screening for prostate cancer do not outweigh the harms. Earlier, in 2008, the federal task force had recommended that men over the age of 75 stop being screened.
In one of the new studies, researchers used data from the National Cancer Institute’s Surveillance, Epidemiology and End Results (SEER) records, to show that prostate cancers dropped from 535 per 100,000 men (50 and older) in 2005 to 416.2 per 100,000 men in 2012, with the biggest drop happening between 2011 and 2012.
Further, and perhaps not surprisingly, the study showed that rates of PSA screening for men 50 years and older dropped by 18 percent between 2010 and 2013, reflecting, it would seem the new USPSTF recommendations, which discouraged the use of prostate-specific antigen (PSA)-based screening for average-risk men.
The second study, conducted by researchers from three medical centers, reiterated the decline in the amount of men getting PSA screening after the release of the 2012 USPSTF guidelines.
Is this good news or bad news for men concerned about their prostate health?
According to public health researcher Dr. Ruth Etzioni of Fred Hutchinson Cancer Research Center, it’s too soon to tell.
“These results don’t really have any implications for men at this point,” said the longtime biostatistician, whose research specifically focuses on the effectiveness of screening for both prostate and breast cancers.
“If people are being more circumspect about prostate screening, that is a good thing,” she said. “If this ends up leading to higher prostate cancer mortality, then it will be a concern. But we don’t know that yet.”
Prostate cancer is the second leading cause of cancer deaths among men in the U.S., second to only lung cancer, according to the American Cancer Society. This year alone, 220,800 new cases of prostate cancer will be diagnosed and about 27,500 men will die of the disease.
Much like mammography, PSA screening needs to be used smartly, Etzioni stressed.
“You have to be smart about screening and smart about treatment,” she said. “And part of screening smartly means recognizing that you don’t need to treat all cancers. For both breast and prostate cancers, people tend to put a lot of faith in screening and overestimate how much it can do and they also tend to downplay the potential harm.”
With prostate cancer, that harm includes overtreatment for so-called "indolent” or nonlethal cancers which can result in men not only going through the anxiety of a cancer diagnosis, but undergoing unnecessary surgeries and treatment that can leave them incontinent and/or impotent.
“Those are real side effects of treatment,” said Etzioni.
An editorial accompanying the two studies, written by Dr. David Penson, chairman of urologic surgery at Vanderbilt University Medical Center, pointed to the potential harm that can result if fewer men undergo PSA screening, though.
“Certainly, physicians have been overly aggressive in their approach to prostate cancer screening and treatment during the past two decades,” he wrote. “But the pendulum may be swinging back the other way. It is time to accept that prostate cancer screening is not an ‘all-or-none’ proposition and to accelerate development of personalized screening strategies that are tailored to a man’s individual risk and preferences.”
Dr. Jonathan Wright, who researches prostate cancer at Fred Hutch and treats prostate patients at Seattle Cancer Care Alliance, said he tries to help his patients understand that there is no one-size-fits-all approach to prostate cancer screening or treatment.
“The PSA cannot tell aggressive from nonaggressive cancer,” he said. “It can flag if there’s a risk for cancer but the majority of men with mild elevations in PSA don’t have cancer. It’s not a definitive test by any stretch.”
Even if a patient’s baseline PSA is significantly changed or elevated, Wright said he will repeat the PSA test before jumping to a biopsy. He will also plug family history, age and other key information into a risk calculator to give a more precise picture of a man’s risk.
“Before I biopsy someone,” he said, “I always tell them, ‘Here’s the chance we’ll find no cancer, here’s the chance we’ll find low-risk cancer for which I’ll likely recommend no treatment but active surveillance and here’s the chance we’ll find aggressive cancer where I’ll recommend active treatment such as surgery or radiation.”
Active surveillance, he said, involves scheduled follow-up blood tests, follow-up exams and follow-up biopsies.
“If we see a change and the cancer is becoming larger or more aggressive, we then intervene with curative intent, thus sparing many men the overtreatment," he said. "But you have to plant the seed that there are cancers out there that we are going to watch.”
Etzioni, who recently helped create the new American Cancer Society breast screening guidelines for average risk women, also acknowledged the importance of a personalized approach.
“You want to identify the people who are going to be less likely to need [screening],” she said, pointing to the importance of stratifying people’s individual risk. “You can get a better trade-off of harms to benefits.”
She also expressed compassion for the men and women caught in the middle of these ongoing screening debates.
“These are very sensitive issues,” she said. “Breast and prostate cancers are hot buttons for women and men for many reasons. Many people have strong feelings about them, particularly survivors who have found their cancer through screening. But the thing is, we can’t screen everybody all the time. We have to use it smartly and try to get the biggest bang for our buck. That’s what the ACS guidelines panel was saying with regard to breast cancer screening and what the Task Force is trying to do with prostate cancer, as well.
“Overdiagnosis and overtreatment can definitely be detrimental, too,” she said. “It’s all about quality of life.”
Wright, who will begin recruiting for a new prostate study involving active surveillance coupled with healthy lifestyle changes, said there are new screening tools coming down the pike but added, “we don’t have the perfect test yet.”
The key take home message at this point, he said, is shared decision-making.
“You really need to have a discussion between doctor and patient and look at your risk profile and understand the pros and cons of PSA screening,” he said. “There’s no right answer for everybody.”
Solid tumors, such as those of the prostate, are the focus of Solid Tumor Translational Research, a network comprised of Fred Hutchinson Cancer Research Center, UW Medicine and Seattle Cancer Care Alliance. STTR is bridging laboratory sciences and patient care to provide the most precise treatment options for patients with solid tumor cancers.
Diane Mapes is a staff writer at Fred Hutchinson Cancer Research Center. She has also written extensively about health issues for nbcnews.com, TODAY.com, CNN.com, MSN.com, Columns and several other publications. She also writes the breast cancer blog, doublewhammied.com. Reach her at firstname.lastname@example.org.
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