University of Virginia Health System

U.VA. OFFERS NEW, IMPROVED CERVICAL CANCER TEST

A new test for cervical cancer is now offered at the University of Virginia Health System, thanks to a collaborative study involving researchers at the National Cancer Institute (NCI), U.Va. and several other universities. The test clarifies which women are at higher risk for cervical cancer and need to have additional tests after a mildly abnormal Pap smear.

It's a big step toward making cervical cancer preventable, said Dr. Mark H. Stoler, professor of pathology and clinical obstetrics and gynecology at U.Va., who worked with the NCI researchers to determine the benefits of combining testing for human papillomavirus (HPV) with traditional Pap tests to test women's risk for cervical cancer.

HPV is a factor in more than 95 percent of cervical cancer cases. However, up until now, the utility of testing for HPV was not well defined. Because of this uncertainty about whether it was useful some women, who really were at risk, may have gone unidentified. Others were tested unnecessarily because of false positive results from their Pap smears who really did not need the additional tests. The NCI trial has clarified the situation. The data clearly demonstrate that patients with the most common form of mild abnormality on Pap smear can be effectively triaged by the HPV test.

Instead of a conventional Pap smear, the new ThinPrep® test collects sample cells from the cervix into a vial of liquid that can be more accurately processed in a laboratory, where pathologists and technicians filter the sample to remove blood and mucus, leaving only cervical cells to examine. If a woman with this type of Pap test has an equivocal diagnosis, known as atypical squamous cells of undetermined significant (ASCUS), then a second test for HPV can be performed on the left over material. If this reflex HPV test is negative, the patient has a less than one percent chance of having a high grade, precancerous lesion, providing great reassurance to the patient and her doctor that the cellular changes are not serious, Stoler said. In contrast, a positive HPV test more effectively predicts whether the patient has a truly precancerous lesion that needs further diagnosis and treatment.

Although the combination of ThinPrep® and HPV testing is more expensive than just a Pap smear, it reduces the number of more expensive tests that might have been done unnecessarily following a Pap smear, such as a serial repeat visits or colposcopy, where tissue is magnified so it can be selected for removal as a biopsy sample. The ability to save unused portions of a single sample for additional testing if need, saves patients office visits making the whole process more convenient and efficient

All physicians at U.Va. Health System who provide Pap tests now use the FDA-approved ThinPrep® test and can order reflex HPV testing for their patients with equivocal Pap results.

March 28, 2002