Cervical cancer screening guidelines largely align, with one exception

May 19, 2015

Clinical guidelines recently put forth by the American College of Physicians indicate that Pap tests should remain the mainstay of cervical cancer screening in average-risk patients under the age of younger than 30 with HPV testing reserved for older patient populations.

An updated set of guidelines for cervical cancer screening recently put forth by the American College of Physicians (ACP) were found to be largely in line with those currently suggested by other groups, underscoring the overwhelming consensus in the management of this patient population.

In average-risk women older than 65 years of age, the ACP guidelines suggest that cervical cancer screening should be stopped if patients had 3 consecutive negative Pap tests or 2 consecutive negative Pap tests plus human papillomavirus (HPV) test results within 10 years, with the most recent test performed within 5 years.

Cervical cancer was once one of the most common causes of cancer death for American women. However, the numbers of cervical cancer cases and cervical cancer deaths have significantly decreased over the last decades due to continued research in the pathogenesis of the disease as well as improved screening methods.

Many different risk factors are associated with the development of cervical cancer, including smoking, immunosuppression, and long-term use of oral contraceptives, but perhaps the most important risk factor of all is infection by HPV. Human papillomavirus, particularly HPV types 16 and 18, is found in more than 99% of cervical cancers and has been consistently implicated in the development of the disease. However, the appropriate time frame in which a patient should be screened and which screening tools should be implemented have been recent subjects of debate among specialists.

The Pap test is seen as one of the most important screening tools available, as it not only can find changes in the cervix before cancer develops but can also help in finding cervical cancer early, in its most curable stage. Tests for cancer-causing types of HPV have recently taken center stage as an important screening tool for cervical cancer, given the clear associations established between the disease and HPV infection.

“Pap smears are the foundation for cervical cancer screening, but there is an option to add an HPV test to women aged 30 and older, mainly in a way to define a group of women that are at very low-risk of cervical cancer. If both Pap and HPV testing are negative, women can be screened less often than every 3 years,” said George F. Sawaya, MD, Professor of the Department of Obstetrics, Gynecology and Reproductive Sciences at the University of California San Francisco, director of San Francisco General Hospitals' Colposcopy and Cervical Dysplasia Clinic, and lead author of the recent ACP guidelines paper. 

The current recommendations of the ACP dictate that this group of women could be screened every 5 years instead of every 3 years. According to Dr. Sawaya, the reasoning is that current cervical cancer screening strategies are more about trying to find cancer in the low-risk women rather than trying to find women who may be marginally higher-risk, which could lead to more intensive screening and further, to unnecessary interventions such as biopsies and cervical treatments.

“There are certain concerns with over-screening patients for cervical cancer because the more we screen the more we find, and the more we find the more likely we could get false positive test results. Precancerous cervical lesions can undergo natural regression so the more we screen, the more likely we will over-treat women for lesions that will go away on their own,” Dr. Sawaya said.

In the ACP guidelines, average-risk women were defined as those with no history of precancerous lesions or cervical cancer; those who are not immunocompromised; and those without in-utero exposure to diethylstilbestrol. According to Dr. Sawaya, the ACP guidelines largely reinforce those suggested by other groups including the US Preventive Services Task Force (USPSTF), the American College of Obstetricians and Gynecologists (ACOG), and the American Cancer Society (ACS). While the ACS and ACOG suggest that HPV testing plus Pap test in women aged 30 and older be the preferred strategy to Pap tests alone, the ACP and USPSTF do not recommend HPV testing plus Pap tests preferentially in this patient population.

Nevertheless, the consensus seen among the different guideline groups is very welcome, Dr. Sawaya said, as physicians appear to be approaching patient screening that maximizes benefits and minimizes potential harms.

“Some women prefer not to have frequent screening and if there are little enough risks to not have them tested as frequently as every 3 years, then that would be valuable information for those women. For average-risk women, clinicians should strive to be as adherent to the guidelines as possible,” Dr. Sawaya said.