Cervical Cancer Screening: Docs Unconvinced on HPV DNA Test
The US Food and Drug Administration recently approved the use of a human papillomavirus (HPV) test as a primary cervical cancer screening test in women as young as 25 years, yet physicians are unlikely to ditch the Papanicolaou (Pap) test soon, experts say.
Roche's cobas test is 1 of 4 HPV tests on the market, but thus far it is the only one approved for primary screening, rather than for use in conjunction with Pap tests.
The cobas test was initially approved in April 2011 for women aged 21 to 29 years who had an abnormal Pap test and as a "co-test" with the Pap test for women aged 30 to 65 years. The test detects DNA from HPV 16 and HPV 18, the 2 types of HPV that cause 70% of cervical cancer cases worldwide, as well as for DNA from 12 other high-risk types of HPV.
If the cobas test is used as a primary screen, those who test positive for HPV 16 or HPV 18 are supposed to have a colposcopy, according to the FDA. If they test positive for 1 of the other high-risk HPV types, they are supposed to have a Pap test to determine whether they need colposcopy.
"I don't know that we're going to see an immediate change in how patients are screened for cervical cancer," Levi Downs, MD, a spokesman for the Society of Gynecologic Oncology and an associate professor of obstetrics and gynecology at the University of Minnesota School of Medicine, Minneapolis, said to Medscape Medical News.
"We have such a good test now," Dr. Downs said, referring to the Pap test, which physicians first began using in the 1940s. "We know that it has dramatically changed the impact of cervical cancer. Physicians, I think, are going to take their time in deciding what the data (about primary screening with an HPV test) mean."
Despite its approval, critical questions remain unanswered about the HPV test as a primary screening tool for cervical cancer, David Chelmow, MD, chair of obstetrics and gynecology at Virginia Commonwealth University in Richmond, told Medscape Medical News. For example, should women be screened more frequently or less frequently than current guidelines recommend for the Pap test? How should women aged 25 through 29 years be screened, given that the FDA approved cobas as a primary HPV test for those as young as 25 years, but current guidelines advise against routine use of an HPV test in women younger than 30 years? In addition, researchers do not yet know whether primary screening with the cobas test will lead to an increase in colposcopy and cervical biopsies compared with Pap screening.