Most women only need to be screened for cervical cancer once every three years, according to a new set of practice guidelines that the American College of Physicians, a national organization of doctors, released today. Women under the age of 21 shouldn't undergo testing at all — regardless of their sexual health history — because many will receive abnormal test results without ever developing cervical cancer.
While preventive screening seems like a positive thing, testing too often can lead to an increased incidence of false positive results — saying some women are sick when they aren't. Follow-up tests increase health care costs and can sometimes lead to pain. Right now, about 60 percent of women in the US say that they were screened cervical cancer by the age of 21.
Yearly testing "does not lead to better care."
"Screening more than once every three years does not lead to better care — it’s unnecessary care," says Tanveer Mir, physician and Chair-elect of the Board of Regents of the American College of Physicians. Despite similar guidelines issued by other agencies, doctors are still screening patients annually, she says — and that shouldn't be the case. "Overall the focus of these guidelines is that physicians can practice good care by reducing over-treatment."
In most cases, cervical cancer is the long-term consequence of infection with a high-risk type of human papillomavirus (HPV) — a sexually transmitted infection. An estimated 13,000 women will be diagnosed with cervical cancer in the US this year, and 4,100 will die from the disease. But the overall incidence of the condition has decreased over the past few decades, largely because of increased screening.
Screening is expensive, though — in 2010, the direct medical cost for screening and follow-ups was $6.6 billion. And, as researchers hone in on what factors increase a woman's cervical cancer risk, they've also come to realize that yearly screenings for women who don't have a history of cervical cancer or a weakened immune system doesn't make much sense — especially given the health risks associated with over-testing.
Over-testing can lead to false positive results, and negative health consequences
Testing can cause short-term anxiety, as well as physical discomfort — which sometimes leads to bleeding, Mir says. False positives can lead to long periods of unnecessary surveillance, as well; women who receive an abnormal test result that doesn't lead to treatment are watched carefully, regardless of their age. More frequent testing — yearly testing — means treating or monitoring some young women whose cervical lesions would have regressed on their own. "And there are [negative health consequences] tied to that, like pregnancy complications," such as increased risk for pre-term birth, Mir says.
That's why recommendations like the ACP's matter. They're designed to let physicians and their patients know that, in most cases, yearly testing for cervical cancer is overkill. "I was thrilled to see that it reinforces the evidence base and consensus around US cervical cancer screening among women in the general population," says Jane Kim, a health policy professor at Harvard University who specializes in women's health. It "really drives the message home to providers and patients that 'more' is not necessarily 'better.'"
"I was thrilled."
The ACP's new guidelines are geared toward "average-risk women," meaning women who have no prior history of precancerous lesions or cervical cancer. Average-risk women also include women who don’t have a weakened immune system — because of an HIV infection, for instance — as well as women who weren’t exposed to synthetic estrogen as fetuses, as practice that was popular between 1940 and 1971. Today's guidance is in agreement with previous guidelines issued in 2012 by the American College of Obstetricians and Gynecologists, the American Cancer Society and the US Preventative Services Task Force, among others.
Women under 21 don't need to be screened at all, the guidance says. Past the age of 21, clinicians only need to screen average-risk women once every three years. And they should do so using the pap smear — a test that scrapes cells from the cervix. For women over 30, clinicians can safely lengthen the testing cycle to once every five years, using a combination of the pap smear and the HPV test. Average-risk women over the age of 65 can stop getting tested altogether if they have had three consecutive negative pap smear results or two consecutive negative HPV tests.
Doctors haven't done a very good job of explaining to women that they don't need get tested every year, the guidelines say. In fact, they haven't changed their behavior to respond to the American College of Obstetricians and Gynecologists' guidelines, released in 2012. Doctors often begin screening too early, and perform screening too often, the ACP's report notes.
"As physicians, we need to do a better job trying to tell patients when screening should start," Mir says. "The primary care physicians and gynecologists, all of us are in the same boat where we have to do a better job of educating our patients."