Women being screened too often for cervical cancer

By Dr. Ananya Mandal, MDAug 18 2011

A new study shows that most doctors are opting to screen women for cervical cancer more often than guidelines suggest.

Researchers based at the Centers for Disease Control and Prevention (CDC) found that many primary care doctors would bring women back for cancer screening annually - while recommendations generally call for a three-year wait after normal tests. This translates to higher costs to women and the healthcare system, as well as a risk of unnecessary treatment for false-positive test results - with very little additional cancer-catching benefit say experts. Lead author Katherine Roland said, “There's really no advantage to annual screening compared to screening every two or three years.”

Guidelines from the American Cancer Society and other organizations recommend that women age 30 and older are screened using Pap smears and tests for the human papillomavirus, or HPV. For younger women, the ACS recommends starting testing at age 21 or three years after beginning sexual activity. If both tests are normal, those guidelines call for a three-year wait before the next screening. That's because HPV - which causes changes in the cervix that can lead to cancer - may take a decade to progress to that point.

“No test is perfect,” said Philip Castle, an HPV expert at the American Society for Clinical Pathology in Chicago. But, he added, “a single negative HPV test is very good at ruling out disease.” Even when doctors use just a Pap test, Roland said, a woman who has had a few normal tests in a row can go two or three years before her next screening.

For this new study the team sent out questionnaires to a representative sample of about 600 office-based doctors and hospital departments around the country. They asked doctors and staff what tests they used for cervical cancer screening and presented them with three patient scenarios.

In those scenarios, a woman age 30 to 60 has had two consecutive normal Pap tests but no HPV tests; two normal Paps and a negative HPV test; or a negative HPV test but no recent Pap tests.

In all of those cases, guidelines recommend waiting three years before screening the patient again, the authors explain in the American Journal of Obstetrics & Gynecology. But for each scenario, between 67 percent and 85 percent of doctors said they would bring the woman back in a year.

Results from a survey of the same doctors have shown that many also give the HPV test alongside Pap smears to women under 30 - which is not recommended, because HPV is common in young women and often goes away on its own. Castle said there could be a few reasons that doctors opt to screen women more often than is recommended. First, they might not know about the guidelines. But women may also be used to annual testing and ask for it themselves. In addition, Roland added, some doctors might be afraid of missing very early cervical cancer and getting sued if they screen less frequently.

But if doctors and hospitals want to rein in spending and limit unnecessary risks, that attitude has to change, researchers agreed. “We need to shift toward the wellness visit as opposed to, 'You have to come in here every year for a Pap,'” Castle said. Women should talk to their doctors about screening, especially if they think they are being screened too often, researchers added.

“A woman should know what test is being used,” said Dr. Mona Saraiya, a co-author on the new study. “Often a provider just does the HPV test” without telling the patient. “A woman should say, 'What screening tests are you doing on me?'” And if doctors want women to come back again next year, women should ask them why, Saraiya said.