A new DNA test has been developed by Qiagen to identify the human papillomavirus (HPV), a virus found to be associated with cervical cancer. Scientists state that this new test is an improvement on current testing methods and might eventually replace the Pap smear test as a way to diagnose HPV.
Early diagnosis is key in fighting all types of cancer, including cervical cancer. In fact, the most common pitfall doctors fall into regarding patients with cancer is failing to diagnose cancer early enough to provide treatment. This new test could reduce the number of missed cervical cancer cases and improve cancer patients’ outcomes.
The optimism around this new DNA test is based on the results of an 8-year study of 130,000 women in Indian that was recently published in the New England Journal of Medicine. The study, financed by The Bill and Melinda Gates Foundation, revealed that a single screening with the DNA tests met all the same standard as all other methods of early diagnosis of cancer.
Similarly, a study by the University of Chicago reports that a predictive model based on family history of breast or ovarian cancer can aid genetic counselors in diagnosing breast cancer in African women. Development of genetic testing for different ethnicities is important because research shows that genetic mutations vary among racial and ethnic groups.
Some experts predict that with this new DNA test, female patients over 30 years-old could stop taking annual Pap smears and instead get the DNA test once every 3, 5, or 10 years. Yet whether the new DNA tests will be adopted as the only method for cervical cancer screening may depend on the degree of hesitation by gynecologists to abandon Pap smears. As the use of Pap smears have increased over the past several decades they have proved to be remarkably effective. Cervical cancer was a leading cause of death for American women in the 1950s and now kills fewer than 4,000 a year.
Scientists know that cervical cancer is caused by just a few of the 150 strains of HPV. Women pick up strains of HPV as soon as they start having intercourse, but over 90% of these cases clear up on their own within 2 years. Early DNA testing would find all of these strains and could lead to over treatment of noncancerous cells. Currently doctors are in the practice of ordering repeat Pap tests for women aged 20 to 30 who have abnormal results. This method can get expensive, but may catch the tiny minority of cancers that develop from HPV.
One of the advantages to the new DNA test is its cost. And cost is a major factor in poor and middle-income countries where the cancer kills more than 250,000 women a year. With additional financing from the Gates Foundation, Qiagen has developed a $5 version of its test and expects that the price could be reduced further if there were a significant number of orders. A 2-year study in China showed that the $5 test was effective. The test runs on batteries, does not need any water to work, and takes less than 3 hours to come up with results.