FDA OKs Expanded HPV Test for Women
Test Detects High-Risk Viruses That Can Cause Cervical Cancer
April 2, 2003 -- Like the Pap test, a test for HPV -- human papillomavirus -- could soon be an annual event for women over age 30. The FDA has expanded its approval of a new test for this virus, which causes most cases of cervical cancer.
Cervical cancer will strike over 12,000 American women this year and kill 4,100, according to the American Cancer Society. It usually grows slowly, so regular Pap smears can catch it early -- often, when cells are just beginning to turn cancerous. Early detection can help doctors cure or even prevent cervical cancer.
However, Pap tests are often inconclusive, showing abnormal cells that may or may not be precancerous.
HPV -- which has long been linked with cervical cancer -- is one of the most common sexually transmitted infections, says an FDA statement, with an estimated 20% of the sexually active U.S. population infected with HPV at any one time.
Most women who become infected with HPV are able to naturally fight off the virus and suffer no apparent long-term health problems. But a few women develop a persistent infection that can eventually lead to pre-cancerous changes in the cervix.
Three years ago, the FDA approved a limited use of the HC2 High-Risk HPV DNA Test, manufactured by the Digene Corp., of Gaithersburg, Md., for women who had abnormal Pap test results. The HPV test results helped determine whether the women needed to be referred to a specialist for further examination.
This expanded FDA approval allows the test to be used for screening of all women over age 30. Along with the Pap test, a complete medical history, and an evaluation of other risk factors, it will help doctors determine if any kind of follow-up is necessary.
In the HPV test -- like the Pap test -- the doctor takes a swab of cells from the cervix. The cell swab is then sent to a laboratory for analysis. While there are more than 100 types of HPV, this test can identify the DNA of 13 high-risk types even before there are any visible changes to the cells on the cervix.
However, the test does not test for cancer, says the FDA statement. It only tests for the HPV viruses that can cause cell changes in the cervix. If not treated, these changes can eventually lead to cancer in some women.
"Knowing whether or not a woman is infected with high-risk HPV is added information that will help physicians detect and treat early cell changes that might eventually lead to cervical cancer," says FDA commissioner Mark B. McClellan, MD, PhD, in a news release.
Women who have normal Pap test results -- and no HPV infection -- are at very low risk for developing cervical cancer. Women who have an abnormal Pap test -- and a positive HPV test -- are at higher risk for cervical cancer. In fact, their risk is 7% or higher than women with normal test results.
The HPV test is not a substitute for the Pap test -- and is not intended for women under age 30 who have normal Pap tests, says the FDA statement. Although the rate of HPV infection in this group is high, most infections are short-lived and not associated with cervical cancer.