New Technology for Cervical Cancer Screening and Diagnosis
Because the Pap test can be associated with sampling and interpretation errors, research and development strategies are focused, to a large degree, on fine-tuning Pap test interpretation, visualization and tissue retrieval. The U.S. Food and Drug Administration has approved a number of devices to enhance the Pap test. Here's an overview of the new technology designed to improve accuracy of the Pap smear:
Newer liquid-based Pap tests such as ThinPrep and SurePath use a solution that helps preserve the cells scraped from the cervix (the Pap smear), as well as remove mucus, bacteria and other cells from the specimen that may interfere with examining the cervical cells. Test vials preserve specimens for up to three weeks from the date of collection, giving the physician an opportunity to request HPV testing on a patient if a borderline Pap test results.
The tests improve the detection of many lesions and reduce the need for unnecessary repeat tests.
Other technology includes:
AutoPap 300 QC Automatic Pap Screener System: a fully automated quality control system that re-screens all Pap smear slides for fewer false negative results—when tests fail to detect existing abnormalities.
Cervicography: creates enlarged photographs of the cervix to be used along with Pap tests.
papnet Testing System: a computer system that selects the 128 worst cells obtained by the Pap test for evaluation by a cytologist.
papSure: a cervical screening device with a tiny light attached to the speculum that enables a health care professional to directly visualize abnormalities at the time of the pelvic exam. The blue light on papSure is designed to cause abnormal tissue to appear bright white.
Pathfinder System: an automated computer-based microscope that helps cytotechnologists identify, mark and record suspicious cells on Pap tests.
These tests were designed to more accurately interpret Pap smear slides and to reduce the incidence of false negative results.
Because some HPV subtypes can be a predictor of the presence or future development of cervical cancer, many medical professionals now also test for this disease as an adjunct to the Pap test. One test now available is:
Hybrid Capture II. This test uses DNA-based technology to detect HPV. It can be performed at the same time as a Pap test and in the same manner, with a swab of cells scraped from cervical tissue. In March 2003, the FDA expanded the use of the test to include screening, in conjunction with the Pap test, of women over age 30 for HPV infection. It should be used along with a complete medical history and an evaluation of other risk factors to help physicians determine what kind of follow-up to the Pap may be necessary.
To help improve the reliability of your Pap test, schedule your appointment two weeks after your last menstrual period and refrain from doing the following for at least 48 hours before the test:
- Having sex
- Using tampons
- Using vaginal creams, suppositories, medicines, sprays or powders