Cervical cancer screening: Less testing, smarter testing
ABSTRACTIn its 2009 recommendations for cervical cancer screening, the American College of Obstetricians and Gynecologists (ACOG) calls for less-frequent but smarter screening that integrates testing for human papillomavirus (HPV) infection with the Papanicolaou (Pap) test. We review the recommendations from this and other organizations and how and why they are evolving.
KEY POINTS
- Persistent infection with one of the 18 high-risk types of HPV is associated with the development of nearly all cases of cervical cancer.
- The 2009 ACOG guidelines recommend starting to screen with the Pap test at an older age (21 years) than in the past, and they recommend a longer screening interval for women in their 20s, ie, every 2 years instead of yearly.
- Women age 30 and older should undergo both Pap and HPV testing. If both tests are negative, screening should be done again no sooner than 3 years. Alternatively, women age 30 or older who have had three consecutive negative Pap tests can be screened by Pap testing every 3 years.
- Although vaccination can prevent most primary infections with high-risk HPV, it does not eliminate the need for continuing cervical cancer screening, as it does not protect against all high-risk HPV subtypes.
- Screening can stop at age 65 to 70 in women who have had three negative Pap tests in a row and no abnormal tests within the past 10 years.
HPV VACCINATION DOES NOT MEAN THE END OF SCREENING
The development of an effective HPV vaccine and FDA approval of the first quadrivalent (active against HPV 6, 11, 16, and 18) recombinant vaccine (Gardasil) in 2006 has opened a new era of cervical cancer prevention.73,74 At present, the Advisory Committee on Immunization Practices75 recommends vaccination for females 9 to 26 years old.
However, HPV vaccination will not make screening obsolete, since not all women will be vaccinated, and those who have already contracted one of these high-risk HPV types will not benefit.76,77 In addition, the current HPV vaccine does not protect against infection with other oncogenic HPV types. The experts estimate that the initial impact of the HPV vaccine on cervical cancer will not likely be apparent until at least 20 to 30 years after a nationwide vaccination program is implemented.78,79 Therefore, the HPV vaccine certainly does not portend the end of screening. Vaccination combined with continued screening will provide added benefit for cervical cancer prevention.80
The last decade has been an exciting period in the field of cervical cancer screening and prevention, with advances in technology, newly acquired knowledge, and the development of the HPV vaccine. As a result, our clinical practice has become a work in progress, continuing to evolve as we continue to discover more information. The possibility of eradicating cervical cancer has never been greater. The implementation of the most sensitive and effective screening strategy and of a worldwide HPV vaccination program will help us to eventually eradicate cervical cancer and make it a disease of the past.81
