New methods for accurate results.

What methods are being developed to improve the accuracy of Pap tests?

In April 1996, the Consensus Development Conference on Cervical Cancer, which was convened by the National Institutes of Health (NIH), concluded that about half of false negative Pap tests are due to inadequate specimen collection.

The other half are due to a failure to identify or interpret the specimens correctly. Although the conventional Pap test is effective in the majority of cases, the conference made it clear that new methods of collecting and reading specimens are needed to reduce the number of false negatives.

The Bethesda System requires laboratories to determine whether there are enough cervical cells in the specimen to make a proper evaluation. This requirement helps improve the quality of samples and sample collection. The Bethesda System requires a sample to be categorized as “satisfactory for evaluation” or “unsatisfactory for evaluation.”

One new method of collecting and analyzing samples is called liquid-based thin-layer slide preparation. This method may make it easier to screen for abnormal cells. Cervical cells are collected with a brush or other collection instrument.

The instrument is rinsed in a vial of liquid preservative. The vial is sent to a laboratory, where an automated thin-layer slide device prepares the slide for viewing. Results of this method suggest that it is comparable to, or more sensitive than, standard Pap tests for the detection of significant abnormalities.

Computer automated readers are also being used to improve the reading of Pap tests. This technology uses a microscope that conveys a cellular image to a computer, which analyzes the image for the presence of abnormal cells.

• Develop molecular classifi cations of cervical cancer subtypes to aid disease prognosis and help in the design of individualized treatment strategies.

• Conduct population-based studies of quality of care and short- and long-term outcome, with a special emphasis on health disparities.

• Characterize the molecular and cellular pathways in cervical cancer cells and their microenvironment, with emphasis on the effects of hormonal and immune systems on cancer development. Use this knowledge to develop molecular strategies for prevention, early detection, prognosis, and treatment.

• Continue research on vaccines for both the prevention and treatment of cervical cancer.