It’s been two months since a government task force recommended against doctors routinely ordering prostate cancer screening tests. But many physicians disagree with the new guidelines, leaving men in a quandary: Should they continue to be screened with a prostate-specific antigen (PSA) blood test and digital rectal exam beginning at age 50, or should they skip the screening altogether? Some doctors still order a PSA without asking their patients, others have in-depth discussions to reach a shared decision, and still others decline to offer it at all.
The dilemma arises from the unique nature of prostate cancer — a common diagnosis that occurs in one out of every six men, but that isn’t lethal in most cases. As many as two-thirds of men diagnosed with prostate cancer have low-risk tumors that are small and slow-growing, yet nearly 90 percent of them immediately undergo harsh treatments including surgery or radiation, which can cause permanent side effects such as urinary incontinence or impotence. PSA testing and the biopsies that follow abnormal screening results often can’t distinguish between non-life-threatening tumors and those that will spread and kill a man, which leads to overtreatment.
“It’s always hard to stop something you’ve started,” said Dr. Leigh Simmons, an internist at Massachusetts General Hospital. “Before patients even get PSA screening, we need to talk about what we’re going to do if it comes back elevated.”
The task force’s new recommendation was based on the latest research showing that PSA screening saves few, if any, lives and that it has an overall net negative impact, leading to overtreatment of slow-growing cancers and resulting side effects.
While experts debate the merits of screening all men over age 50 for prostate cancer, most agree that the PSA test has significant flaws, both detecting too many harmless cancers and missing lethal growths. For every 100 men who get a PSA test, three will have real cancers detected and two will have cancers that are missed, according to the American Society of Clinical Oncology. Another five will have false positive results that may warrant a biopsy that turns out to be negative for cancer.
Some prostate cancer experts, however, say it’s not a question of whether to abandon PSA screening altogether but to find the most appropriate men to screen.
Of those real cancers detected via PSA screening, most men who have their tumors surgically removed enjoy no significant life-extending benefits, according to a study published last Thursday in the New England Journal of Medicine. The research, involving 731 men who were screened and diagnosed with early-stage prostate cancer, found that those who had immediate surgery to remove their cancer didn’t live any longer than those who had their cancers regularly monitored for 12 years and excised only if the cancer grew larger or more aggressive. Those with high PSA levels — above 10 nanograms per milliliter — did have a modest reduction in their risk of dying of prostate cancer if they were treated right after diagnosis.
Simmons and her colleagues practice what they call “shared decision-making,” believing it’s their role to help men determine for themselves whether or not to have PSA screening. One of her patients, 82-year-old Peter Albrecht from Newbury, decided to stop PSA screening a few years ago after the same government task force — called the US Preventive Services Task Force — issued a recommendation in 2008 against PSA screening in men over age 75 because of its lack of life-saving benefits. (At that time, the task force also said there was insufficient evidence to recommend for or against screening in men under 75.)
“Dr. Simmons and I discussed my age and that prostate cancer is slow growing and rarely becomes invasive, so it didn’t seem to make sense to continue screening,” said Albrecht.
Simmons has incorporated DVDs into her practice to teach patients about the pros and cons of screening. The video gets into the numbers, such as the potential of regular PSA testing over several decades to lower a man’s lifetime risk of dying from prostate cancer from 3 percent to, at best, 2 percent. On the other hand, the video explains, screening raises a man’s risk of being diagnosed with prostate cancer during his lifetime from 10 percent to 20 percent because it finds tiny cancers that wouldn’t otherwise be detected and likely wouldn’t have been fatal.
When Arnold Wensky heard those odds after watching the video, the 63-year-old decided to continue having regular PSA tests during his annual physical with Simmons in June. “I’m a big believer in screening,” he said, “but if I’m faced with a prostate cancer diagnosis I’m prepared to ask more questions before deciding whether to get treated.”
Some primary care physicians, however, have decided to simply stop offering PSA screening, unless a patient asks for it.
“I haven’t eliminated PSA screening from my practice, but I’m probably ordering fewer tests,” said Dr. Jonathan Berz, a primary care physician at Boston Medical Center. “There are a number of other screening tests, like colon cancer and cholesterol, that have stronger evidence behind them, so I’d rather set aside time to do an in-depth discussion on those.”
Other prostate cancer specialists, however, say it’s not a question of whether to abandon PSA screening altogether but to find the most appropriate men to screen. After all, nearly 30,000 US men will die of prostate cancer this year, compared with nearly 40,000 American women who will die of breast cancer.
“The pendulum has swung too hard in one direction in favor of screening and now has swung too hard in the other, against,” said Dr. William Dale, chief of geriatrics at the University of Chicago Medicine.
Doctors probably don’t need to screen every man over 50, he added, but they should offer screening to those who are at increased risk because they’re African American or have a close family member who died of the disease.
Patient advocate Thomas Farrington, who lost his father and both grandfathers to prostate cancer, firmly believes that PSA screening saved his life when it led to his diagnosis of an aggressive cancer in 2000 at age 55. He founded the Boston-based nonprofit Prostate Health Education Network three years later, with a major focus on urging all African-American men — who are more than twice as likely to die from prostate cancer than whites — to have regular PSA screening beginning at age 40.
“There certainly is overtreatment for prostate cancer,” he said, “but we won’t solve it by sticking our head in the sand and ignoring the benefits of PSA testing.”
Another nuance that some doctors factor in to help patients make informed decisions: life expectancy. “Patients need to have at least 10 more years of life expectancy for them to benefit at all from cancer screening,” said Dale, who does regular assessments with his patients to help them determine which tests and treatments to have. He also found through his research that patients are pretty good at doing their own assessments.
In a study published this year in the journal Geriatric Oncology, Dale and his colleagues found that patients’ self assessments — such as poor, good, or excellent — correlated pretty closely with life expectancy tables and could be used to help patients make decisions concerning PSA screening.