Since the Pap test was first introduced in the 1940’s when cervical cancer was the leading cause of death among women, it has become a preventable cancer as a result of the discovery that the Human Papillomavirus (HPV) is the cause of almost all cases of cervical cancer. This led to the FDA approval in 1999 of a test to detect the cancer-causing types of this common infection and the development of the first vaccine that was approved in 2006.
Even the Pap test itself has been improved. This test involves looking at a sample of cells from the cervix under a microscope to see if there are any that are abnormal. It is a good test for finding not only cancer, but also finding cells that might become cancerous in the future. New techniques allow for the use of the same sample to be used for testing for the cancer-causing types of HPV. Usually healthcare providers perform the Pap test as part of a routine pelvic exam at recommended intervals.
In 2012, the American Cancer Society (ACS), the American Society for Colposcopy and Cervical Pathology (ASCCP), and the American Society for Clinical Pathology (ASCP) released new guidelines for the prevention and early detection of cervical cancer. The guidelines generally advise a reduction in the number of tests women get over their lifetime to better ensure that they receive the benefits of testing while minimizing the harms, and include a preference for co-testing using the Pap test and a highly sensitive HPV test for women age ages 30 to 65.
The updated guidelines recommend:
- Women should not be screened before age 21
- Women 21 to 29 should be screened with the Pap test alone (conventional or liquid-based) every three years. HPV testing should NOT be used for screening in this age group.
- For women 30 and over, the preferred approach is the Pap test plus HPV testing (“co-testing”) every five years. Continued screening with the Pap test alone (without HPV testing) every three years is an acceptable alternative. While screening with HPV testing alone is promising, at this time it is not recommended for most clinical settings.
- Screening is not recommended for women over age 65 who have had at least three consecutive negative Pap tests or at least two negative HPV tests the last 10 years, with the most recent test in the last 5 years. Women in this age group who have a history of cervical pre-cancer (CIN2 or a more severe diagnosis) should continue routine screening for at least 20 years, even if this extends beyond age 65.
- Women who have undergone a hysterectomy (with removal of the cervix) for reasons not related to cervical cancer or pre-cancer should not be screened anymore.
- Women who have been vaccinated against HPV should follow the age-specific recommendations in these guidelines (for unvaccinated women). Currently, there are no alternative screening recommendations for women vaccinated against HPV.
The new guidelines are not intended for women with a history of cervical cancer, exposure to DES during a pregnancy, or women who are immunosuppressed (e.g. HIV positive).
It is important for women to know if a Pap test was performed because it is possible to have a pelvic exam without a Pap test. It is also important that women know and understand their Pap test results and follow through with any recommendations made by their healthcare provider. Some abnormal Pap tests will be followed by colposcopy (examination of the cervix using a magnifying device to see the cervix more clearly) and biopsy of any abnormal appearing areas on the cervix. Any pre-cancerous areas can then be seen and, if needed, treated by a woman’s healthcare provider.
Current cervical cancer screening guidelines state that women with a slightly abnormal Pap test result (called “ASC-US”) and a negative HPV test can be screened again with co-testing in 3 years, or with the Pap test alone in 3 years. Women with a negative Pap result but a positive HPV test can either be rescreened with co-testing in one year, or tested with a test that can determine specific types of HPV (HPV16 and HPV 18).
In 2014, the FDA approved the HPV DNA test for women 25 and older for use alone to help a healthcare professional assess the need for a woman to undergo additional diagnostic testing for cervical cancer. The test also can provide information about the patient’s risk for developing cervical cancer in the future.
Using a sample of cervical cells, the cobas HPV Test detects DNA from 14 high-risk HPV types. The test specifically identifies HPV 16 and HPV 18, while concurrently detecting 12 other types of high-risk HPVs.
Screening for cervical cancer, whether with the Pap test or HPV test, remains a critical prevention step. However, the FDA approval in 2006 of the first vaccine to prevent cervical cancer represents the opportunity to eradicate this cancer. Now there are three vaccines, all given in a series of three injections into the muscle tissue over a 6 month period.
Cervarix targets two HPV types, 16 and 18, and is approved for females ages 9-25. These two high-risk HPV types cause about 70 percent of cervical cancers an even higher percentage of some other HPV-associated cancers.
The FDA approved Gardisil and Gardisil 9 for the prevention of HPV-caused cervical, vulvar, vaginal and anal cancers; precancerous vulvar, vaginal and anal lesions; and genital warts. They also are approved for males for the prevention of HPV-caused anal cancer, pre-cancerous anal lesions, and genital warts. They are approved for females ages 9-26. Gardisil is approved for males ages 9-26 and Gardisil 9 is approved for males ages 9-15.