HPV Test Recommended as Primary Screening Tool

The U.S. Food and Drug Administration's (FDA) Medical Devices Advisory Committee Microbiology Panel voted unanimously in March to recommend approval for Roche's Cobas human papillomavirus (HPV) DNA test as a first-line cervical cancer screening tool for women ages 25 and older. The panel agreed that the test, performed on cells from the cervix, is safe and effective and that the benefits outweigh the risks.

The Cobas test identifies two types of HPV—HPV 16 and 18—which cause most cervical cancers. It also tests for 12 other high-risk types of HPV. It's currently approved as a follow-up test for women 21 and older who have abnormal Pap tests and for use in conjunction with the Pap test for women ages 30 to 65.

If approved by the FDA as a first-line screening tool, the Cobas test could be used alone in lieu of Pap testing. Women who test positive for HPV 16 or 18 would be referred for colposcopy to examine the cervix. A positive test for other high-risk strains of HPV would trigger a Pap test, and women who have a negative HPV test would be followed at their physician's discretion.

The recommendation was based on long-term data from the ATHENA trial, which compared HPV testing to Pap tests in more than 47,000 women and found that HPV DNA testing was significantly more sensitive than cytology.

“The HPV test stacks up very well against the Pap test alone,” says David Chelmow, MD, chair of the department of obstetrics and gynecology at Virginia Commonwealth University in Richmond. “The real question is how does HPV testing alone compare to the current practice of testing with both the HPV and Pap tests.”

Chelmow addressed the FDA panel on behalf of the American College of Obstetricians and Gynecologists, noting that it “strongly supports further improving cervical cancer screening through the introduction of new paradigms such as HPV testing for primary screening.” However, it outlined four aspects of primary HPV screening that need to be clarified: the appropriate intervals for repeat testing, the criteria for ending screening, how to transition patients previously screened with Pap test or a combination of Pap and HPV tests, and how to screen women younger than 25.

Because HPV is a sexually transmitted infection that is relatively common in young women and often resolves without treatment, panelists expressed concern about dropping the recommended age for HPV testing from 30 to 25. They also debated whether HPV testing would lead to an increase in colposcopies, which can negatively affect a woman's reproductive health.

“Colposcopy can lead to biopsies and procedures that can weaken the cervix; however, HPV likely poses a greater risk to these women,” says Chelmow, who points out that more than 99% of cervical cancers are linked to HPV.

Although the FDA typically follows the recommendations of its advisory panels, even with approval, cervical cancer screening practices are not expected to change much until the leading medical societies and organizations update their screening guidelines.