In Canadian research that could eventually change the way women are screened for cervical cancer, a test to identify the human papillomavirus (HPV) was deemed more accurate than traditional Pap exams at detecting precancerous cervical lesions.
The study, which examined test results in more than 19,000 women, was published in a recent issue of the Journal of the American Medical Society (JAMA).
“This is a great study showing the importance of HPV testing as a part of a screening algorithm for cervical cancer,” notes Heather Einstein, MD, a gynecologic oncologist at Hartford Hospital. She adds that the national guidelines currently recommend women undergo HPV and PAP screenings to find pre-cancer and cancer in the cervix, but, “I do think this data will likely be used to influence the next iteration of the guidelines.”
The HPV test, Dr. Einstein explains, screens for certain strains of the HPV virus while the Pap smear involves examining cells from the cervix to see if they are atypical in appearance.
“There are pluses and minuses to both tests,” she admits.
For example, she notes that:
- Many women have been exposed to HPV and will, therefore, have a positive HPV test, but not everyone will get pre-cancer or cancer of the cervix as a result.
- Women may have cervical cells that look abnormal on a Pap smear for reasons other than pre-cancer or cancer.
- Because cancer cells are often necrotic, or dead, they can sometimes be difficult to diagnose on a Pap smear alone.
When the screening methods are indeterminant, women are called back in for more testing, which can be stressful.
“This is why the American Society of Colposcopy and Cervical Pathology developed guidelines that combine the two tests to increase the overall accuracy of cervical cancer screening while decreasing the number of unnecessary follow-up exams and procedures,” Dr. Einstein says.
The Canadian research underscores the importance of the HPV test in this combination, she goes on.
“Almost all – 99.7 percent – of cervical cancers are caused by the HPV virus,” she says. “I would recommend women continue to follow HPV and Pap screening guidelines that call for a combination of the tests at different intervals depending on the woman’s age and history of prior cervical disease.”
Age is important because it is known that older women who have persistent HPV infection are at a higher risk of getting cervical cancer than younger women with HPV. Dr. Einstein notes that the best way to prevent cervical pre-cancer and cancer is to get the HPV vaccine. If a woman already has HPV, the best way to prevent the HPV infection from becoming pre-cancer or cancer is to avoid cigarette smoking and exposure to second-hand smoke.
HPV and Pap smears can be done by your primary care doctor or obstetrician/gynecologist. If you are diagnosed with pre-cancer (dysplasia) of the cervix, your obstetrician/gynecologist can treat you.
If you are diagnosed with cervical cancer, you can find more information about gynecologic oncology at the Hartford HoealthCare Cancer Institute.