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With the advent of HPV vaccination and the emergence of new HPV testing strategies, Maurie Markman, MD, notes, cervical cancer screening and prevention is entering a new era. However, according to Robert A. Burger, MD, FACOG, a woman vaccinated against HPV should still undergo cervical cancer screening. At this point, he explains, the vaccines don’t cover all the pathogenic or oncogenic types of HPV; therefore, screening is still indicated.
This approach to screening may change in the near future with the FDA approval in December 2014 of the 9-valent HPV vaccine. This new vaccine is more comprehensive than the previous vaccine, which only covered 4 strains of HPV. With mass vaccination of both boys and girls with this new vaccine, Warner K. Huh, MD, suggests that a very compelling argument can be made that a) screening can stop altogether, provided that long-term data support this approach, or b) women need to be screened only once in their lifetime.
Unfortunately, the current US HPV vaccination rate is appalling, reaching only 30%, according to Huh. Therefore, until the rate increases and a reliable way of tracking who has been vaccinated is found, Huh and Burger abide by the screening recommendation to manage all vaccinated and unvaccinated women the same way. In the United States, the vaccine is approved for women only up to 26 years of age. Providing the vaccine to women older than 26 years, Huh notes, is essentially an off-label use, and may not be covered by insurance.
Other countries, Huh adds, have approved the vaccine for use in women up to 45 years of age. While there are data suggesting that new disease can be prevented with the vaccination of older women, the benefit is not nearly as great as mass vaccination in the 11- or 12-year-old female population. HPV vaccination is a remarkably effective strategy at a public health level, states Markman, and questions what reasons there may be for not having the vaccination. The major reason, Burger suggests, is sociological.
Another paradigm shift in the cervical cancer setting is the HPV DNA test. The HPV DNA test has the ability to test for all of the oncogenic types at once, explains Burger. It has actually revolutionized HPV testing, he comments, due to its increased sensitivity and specificity. The traditional Pap smear has an approximate sensitivity rate of 50%, adds Huh, versus the HPV DNA test, which has a sensitivity rate of over 95%.
While the cost of the HPV DNA test may be relatively high, with the extended time interval between testing 3 to 5 years, possibly even 10 years, the cost drops dramatically, explains Huh. Another issue, Huh highlights, is that of when to initiate the HPV DNA test. Still, he anticipates that the Pap smear will be used more selectively in the future and that the HPV DNA test will become the favored screening strategy.