Women may be misled about the ongoing need for a Pap test – it is NOT going away
FDA approval of a human papillomavirus (HPV) vaccine is an important step forward in cervical cancer prevention and does create an era of change for cervical cancer prevention. However, the Society of Gynecologic Oncologists (SGO) and the American Society of Cytopathology (ASC) are concerned that recent media reports about the impact of the vaccine on cancer prevention (including a Jan 16, 2007 article by Andrew Pollack titled “Pap Test, a Mainstay Against Cervical Cancer, May Be Fading”) could mislead women to believe that the Pap test is no longer a necessary part of their annual visits to their reproductive health care provider.
The Pap test is not fading in importance today nor is it likely to in the near future. The role of continued cervical cancer screening in a post-vaccine era is still crucial. While being a welcome addition to the fight against cervical cancer, it will be decades before the true impact of HPV vaccines is recognized. As part of the HPV vaccine labeling, the U.S. Food and Drug Administration (FDA) notes that they are not 100 percent effective and the “routine Pap screening remains critically important to detect precancerous changes in the cervix to allow treatment before cervical cancer develops.”
There have been significant improvements in Pap testing during the past several years. Approximately 90 percent of all Pap tests performed in the United States today are “liquid based.” These “liquid based” Pap tests were developed to address significant limitations of the traditional Pap smear. These tests offer better quality and accuracy for women. Multiple trials, peer reviewed published journal articles and FDA approvals have repeatedly demonstrated improved disease detection in a variety of patient populations using these tests. More recently, computer-assisted systems have become available and are widely used. All of this new Pap test technology significantly increases disease detection and reduces false negative rates even further.
HPV testing has also enhanced the accuracy of Pap testing. Especially when a patient’s Pap test is returned with inconclusive results. The addition of HPV testing as an adjunct to Pap test for screening in women 30 years or over is effective for triaging very low risk women to longer screening intervals without significantly changing the effectiveness of cervical cancer screening. The tests in combination, not separately, offer effective conservative management and potentially, cost-effective benefits.
Utilizing HPV testing as a primary screening technique alone has many hurdles to overcome, including lack of prospectively collected clinical trial data and FDA approval to support HPV testing alone for this purpose. The majority of women, as much as 80 percent will be infected with HPV at some point in their lifetime. Since most of these HPV-infected women will not develop cervical disease, a positive HPV test alone does not offer significant clinical value. The high prevalence of HPV infection alone was well described in a recent article by Dunne et al. in the Journal of the American Medical Association (JAMA. 2007;297:813-819). Additionally, much of the data used to promote HPV as a primary screening tool is data based on use of the traditional Pap smear, not the new “liquid based” Pap tests.
Pap testing remains a well-studied, reliable, time-tested and cost effective method of preventing cervical cancer. Since the Pap test went into widespread use in the U.S., cervical cancer deaths have dropped 74%. To suggest that this test, which is one of the best, cost-effective cancer screening test success stories in medical history, is somehow going away, is irresponsible without substantial data sets to prove other methods alone would improve upon these outcomes. SGO and ASC both encourage women to schedule their annual Pap tests today.
Mark Einstein, MD
Chairman, SGO Education Resource Panel
Mary Sidawy, MD