Two revised sets of cervical cancer screening guidelines were released last month—one from a collaboration between the American Cancer Society, the American Society for Colposcopy and Cervical Pathology (ASCCP), and the American Society for Clinical Pathology (ASCP), and a second from the United States Preventive Services Task Force (USPSTF).
Both reports reduce the number of tests recommended for women to maximize the benefits of testing, while minimizing screening risks. The documents also incorporate newer HPV testing along with the traditional Pap test as an alternate screening strategy.
The ACS's Director of Breast and Gynecologic Cancer, Debbie Saslow, PhD, said in a statement, “Since 1980, organizations including the ACS have recommended less frequent screening. With the addition of the HPV test, we can test even less frequently, as the risk of pre-cancer and cancer when both tests are negative is so low.”
The ACS, ASCCP, and ASCP guidelines were published jointly in the organizations' journals, respectively, CA: A Cancer Journal for Clinicians, Journal of Lower Genital Tract Disease, and American Journal of Clinical Pathology (doi: 10.3322/caac.21139). And, the USPSTF recommendations are published in the Annals of Internal Medicine and also available on the USPSTF website (www.uspreventiveservicestaskforce.org).
Key updates to both new sets of guidelines include these screening recommendations by age group:
* Women should not be screened before age 21, regardless of sexual history.
* Women ages 21 to 29 should be screened with the Pap test alone every three years, and HPV testing should not be used for this age group.
* Women ages 30 to 65 should be screened with the Pap test plus HPV testing every five years (“co-testing”), or should continue being screened with the Pap test every three years.
* Women over age 65 should discontinue regular screening if they have had at least three consecutive negative Pap tests (or two negative HPV tests) within the previous 10 years (with the most recent negative test in the last five years). Women in this age group with a history of positive screens or pre-cancer should continue routine screening at least every 20 years.
Saslow noted that because HPV is slow to transition from infection to cancer or precancer, and resulting cancers grow so much more slowly than other tumors, evidence shows there is a less frequent need for screening. “Pap tests have been done yearly in the past, but we now know that annual screening is not needed and in fact can lead to harm from treatment of cell changes that would never go on to cause cancer.”
New Research Prods Updates
Both groups updated their respective guidelines after a comprehensive evidence review of new research on the science of cervical cancer and its relationship to HPV infection. “There was a lot of new science that has been published since the last time the task force released a recommendation,” Michael LeFevre, MD, MSPH, Co-Vice Chair of the USPSTF and Professor and Vice-Chair of Family and Community Medicine at the University of Missouri, said in a phone interview.
The review included two large observational studies published this past year on the effectiveness of HPV testing in addition to Pap smear cytology compared with Pap testing alone. One of the most recent studies, conducted by Kaiser Permanente Northern California, tracked some 330,000 women who had concurrent HPV and Pap testing, and concluded that the method was safe and effective, according to the study published in Lancet Oncology (2011;12:663-672).
“Millions of women every year are getting unnecessary tests and we're not picking up more cancers,” Saslow said in a phone interview. “It's not the women who are getting Pap tests every one to five years who are getting cancer and dying—it's the women who don't get screened at all.” Testing is uncomfortable, can cause pain and bleeding, and can also lead to pregnancy complications like low birth weight, she emphasized.
‘Striking’ Similarities, One Difference
“The consistency between these two recommendations that were published at the same time is striking,” LeFevre said. The slight difference was that for women ages 30 to 65, the ACS, ASCCP, and ASCP recommend the Pap test plus HPV testing every five years rather than the Pap test alone every three years, but the USPSTF guidelines do not indicate any preference for one method over the other.
“The addition of HPV testing to the Pap test in women 30 and over has been shown in recent studies to provide better protection for longer intervals from cancer and pre-cancerous changes than the use of the Pap test alone,” Alan Waxman, MD, ASCCP's Incoming President, said in a statement. Saslow added that new studies on HPV testing show it is a very effective way to detect HPV— “if it's negative, you're not going to have cell changes.”
Cotesting: Concurrent Pap & HPV Testing
THOMAS HERZOG, MD: C...Image Tools
Asked for his opinion for this article, Thomas Herzog, MD, Professor of Clinical Obstetrics and Gynecology at Columbia University Medical Center and the Herbert Irving Comprehensive Cancer Center, said that while cotesting has its advantages, it is still more appropriate for some patients to have more frequent Pap tests.
As for which strategy he would recommend for 30- to 65-year-old women, he said it depended on the patient— “cotesting for the recommended age groups makes sense, since combining an objective and a more subjective interpretative test is reassuring if both are negative. But patients with abnormal Pap results should still get Pap tests every three years.
The difference is very subtle, said LeFevre. “We consider it a tradeoff. I think that women and their health care providers should have a conversation about it and decide what's best for them.”
Either way, the reduction in frequency of testing recommended should not be mistaken for a de-emphasis on the importance that women get the required testing, both LeFevre and Herzog said. “The major way that we can reduce cervical cancer mortality deaths in the United States today is to reach women who are not getting screened,” LeFevre said.
Herzog said that the new recommendations should not discourage women from timely and due screenings. It is time to consider, “will we have less compliance overall as screening intervals become so lengthened that women become remiss in even showing up when they were due? We need to evaluate how the guidelines function in real time.”
© 2012 Lippincott Williams & Wilkins, Inc.