Signaling a potential major change in cervical cancer screening options for American women, a new study found that mailed self-sampling kits that test for HPV—the virus that can cause cervical cancer—helped significantly more women get screened for the cancer.
The study involving nearly 20,000 women was conducted by researchers from the University of Washington and Kaiser Permanente Washington Health Research Institute and was published Nov. 6 in JAMA Network Open.
In the study, women within the Kaiser Permanente Washington system who hadn’t been screened for cervical cancer in more than three years were randomized into two groups: Roughly half were mailed an HPV self-sampling kit that they could complete as an alternative to Pap screening, and the other half received only the standard care reminders to be screened in a clinical setting.
Within the cohort of underscreened women in the self-testing arm of the study, 26% were screened for cervical cancer versus 17% of underscreened women who received the standard reminders. Of those underscreened women who returned the kits, 88% tested negative for the virus, signaling low risk for cervical cancer.
“Many studies have shown that an HPV test on a sample that a woman collects for herself performs as well as an HPV test done on a physician-collected sample,” said lead author Rachel Winer, professor of epidemiology at the UW School of Public Health and affiliate investigator at Kaiser Permanente Washington Health Research Institute.
“Randomized trials in other countries have shown that offering home-based HPV testing increases screening participation, but this was the first U.S. trial to study the impact of mailed kits in a real-world health system setting.”
Half of the 12,000 cervical cancers diagnosed annually occur in women who have gone longer than three years without a screening, according to previous studies. That makes these women a high-priority population to get screened, the researchers said.
“We found that mailing unsolicited self-collection kits for HPV testing increased cervical cancer screening by 50 percent in women who were underscreened for cervical cancer, and that’s a particularly hard population to reach,” said co-author Diana Buist, senior investigator and director of research and strategic partnerships at Kaiser Permanente Washington Health Research Institute.
“So, it’s a good news story,” Buist said. “And now that HPV-only testing is a recognized screening strategy in the United States, it really opens up the possibility for home testing to be a widespread option for women.”
Researchers also wanted to find out whether this high-priority population of women would perform the self-sampling and then, if the sample tested positive for HPV, go in for a follow-up test to determine the presence of precancerous cervical cells that could be treated to prevent cancer.
Unfortunately, they noted, while the vast majority of women tested negative for the virus, not all of the participants who tested positive followed up.
“It’s great that 88% of women who self-sample at home would not need to come into the clinic,” Winer said, “but there’s a key 12% in our trial that were identified to be at increased risk for cervical cancer—and yet only 70% of those women came in for follow-up testing.”
Consequently, the researchers said, additional implementation efforts need to strategize how to increase use of the kit and in-clinic follow-up for positive results to maximize detection and treatment of pre-cancers in high-risk women.
“The landscape of cervical cancer screening in the U.S. is changing, and there is a real opportunity to expand options and improve the screening process for women,” Winer added. “I’m hopeful that a few years down the line, home-based screening will become routinely available.”
The Pap (Papanicolaou) test is a standard screening test that examines cervical cells for abnormal cellular changes indicating cervical dysplasia or cervical cancer. Pap tests have been used effectively in Canada and Manitoba to reduce the incidence of and mortality from cervical cancer. CervixCheck, Manitoba’s organized cervical cancer screening program, was initiated in 2001.
In Manitoba, more than 40% of cervical cancers are found in women who are unscreened (women who have not been registered in the screening program for at least 5 years and who have never had a Pap test)1.
Between 2014 and 2016, cervical cancer screening participation in Manitoba was 66.2% in eligible women, which is well below the participation target of 80% set by the Pan-Canadian Cervical Cancer Screening Network2.
Currently, more than 20,000 women in Manitoba between the ages of 30 and 65 years were sent an invitation letter by CervixCheck, but have no record of a Pap test or colposcopy in the CervixCheck registry. Those unscreened non-responder women are at increased risk for cervical cancer.
Research shows that many barriers prevent women from having a Pap test, including factors at the personal, clinical, and test levels3. Test-level barriers include factors such as physical pain and discomfort or the anticipation of discomfort with a Pap test.
Embarrassment and anxiety are other reasons cited as barriers to having a Pap test4. Although the Pap test is an effective screening test, one of its limitations is low sensitivity—particularly for the detection of non–squamous cell cancers, which constituted approximately 40% of all cervical cancers diagnosed in Manitoba between 2009 and 20161,2.
Strong evidence supports hpv testing as an alternative to the Pap test. The sensitivity of the hpv test is greater than that of the Pap test, detecting persistent hpv infections that can lead to cervical cancer for women more than 30 years of age5,6. Molecular dna testing for hpv detects oncogenic hpv types that can cause cervical cancer and its precursors.
The technology can also be used as part of a screening program in the form of a self-sampling kit for hpv that might be more appealing to under-screened and unscreened women in hard to reach, underserved, or marginalized populations. A self-sampling kit for hpv might also address some test-level barriers to having a Pap test, such as the anticipation of discomfort or pain, or anxiety about having a Pap test in a clinic.
The purpose of the present study was to compare cervical cancer screening participation in unscreened non-responder women in Manitoba who were mailed and not mailed a self-sampling kit for hpv.
More information:JAMA Network Open (2019). DOI: 10.1001/jamanetworkopen.2019.14729
Journal information: JAMA Network Open
Provided by University of Washington