US Survey of Cervical Cancer Screening Finds Good and Bad

Zosia Chustecka

January 03, 2013

A large survey of screening for cervical cancer in the United States shows that over a recent period of 10 years, practice is adhering more closely to guidelines, especially with regard to younger women.

However, the survey also shows that many older women and women who have undergone a hysterectomy are being screened unnecessarily and contrary to current guidelines.

The new findings come from 2 reports released today by the Centers for Disease Control and Prevention (CDC) and published in Morbidity and Mortality Weekly Report.

The reports analyzed data collected from 2000-2010 by the Behavioral Risk Factor Surveillance System on screening for cervical cancer using the Papanicolaou (Pap) test.

One report focused on women aged 18 to 30 years. The CDC reports that 2 favorable trends were seen during the decade: screening was initiated at a later age, and it is being carried out at longer intervals, in accordance with updated guidelines.

Previous guidelines that recommended starting cervical cancer screening at 18 years of age and conducting a test annually are now out of favor. The current evidence-based guidelines call for screening to begin at 21 years of age, with an interval of 3 years between routine Pap tests for women aged 22 to 30 years.

These updated guidelines were issued earlier this year by the American Cancer Society, the American College of Obstetricians and Gynecologists, and the US Preventive Services Task Force.

Data collected in the survey show that these guidelines are making an impact on practice.

From 2000 to 2010, the proportion of women aged 18 to 21 years who had never been screened increased from 26.3% to 47.5%, the CDC notes in its report. Unfortunately, although this shows a growing adherence to guidelines, it also means that around one half of women aged 18 to 21 years are still being screened contrary to guidelines.

Also, among women aged 22 to 30 years, the proportion who reported having a Pap test in the last year decreased from 78.1% to 67%, the agency noted. This means that more than one half of young women aged 22 to 30 years appear to be undergoing screening annually, again contrary to guidelines, which now suggest a test every 3 years.

The CDC also highlights an unfavorable trend among young women: the proportion of women aged 22 to 30 years who report never having been screened rose from 6.6% in 2000 to 9% in 2010.

Unnecessary Testing in Older Women

The other report focused on women aged 65 years and older and on women who have undergone a hysterectomy. Cervical cancer screening is not recommended in either of these groups.

The CDC points out that since 2003, major US organizations have consistently recommended against cervical cancer screening in women aged 65 years or older. But the new data show that such testing is still being carried out, although it is declining.

Specifically, the CDC notes that among women older than 65 years who have not undergone a hysterectomy, screening declined during the decade, from 73.5% in 2000 to 64.5% in 2010.

Routine screening is also not recommended for women who have undergone a total hysterectomy (removal of uterus, including cervix), and this recommendation was agreed upon by the major organizations in 2002/2003. But again, results from the survey show that such testing is being carried out, although it also is declining.

The CDC notes that the proportion of women who reported having a hysterectomy and a recent Pap test (within 3 years) declined from 73.3% in 2000 to 58.7% in 2010.

However, this means that in both groups (women older than 65 years without hysterectomy; women with hysterectomy), more than one half of these women are undergoing cervical cancer screening, contrary to guidelines.

In these 2 groups of women, the net benefits of screening may be outweighed by the net harms, the CDC notes in its report. Such harms can include false-positive tests, leading to needless patient anxiety and invasive procedures.

The CDC estimates that there may be 22 million women with hysterectomies in the United States undergoing screening, contrary to recommendations that have now been in place for longer than a decade. "Research is needed to determine how to further reduce unnecessary screening," the agency concludes.

MMWR. 2012:51,52;1038-1047.