Scientists say using DNA testing and conventional Pap smears could prevent cervical cancer in millions of women worldwide, potentially saving hundreds of thousands of lives each year. A study found the combination testing was most effective in identifying women at highest risk of developing cervical cancer.
In a perfect world, women would go to their doctors every year for a simple test, called a Pap smear, to detect cellular changes over a period of time that lead to cancer of the cervix, or opening to the womb.
But in much of the developing world where fewer resources are devoted to routine medical care, says Eduardo Franco, head of the division of cancer epidemiology at McGill University in Montreal, Canada, Paps are not a very reliable screening tool.
"To you to make an analogy here that the Pap test is just as good as a coin flip in correctly detecting cervical lesions, pre-cancerous lesions, that means to say that the false negative rate is about 50 percent," he said.
Researchers say a genetics test for human papilloma virus, or HPV, is a more effective way of deterring whether a woman is at risk for cervical cancer.
HPV is a sexually transmitted disease that is responsible for cervical cancer.
Because of its sensitivity, Franco says the DNA test could be given every three to five years, instead of annually. The problem is occasionally, the results show a woman is infected with HPV when she's not.
Researchers in Italy found they could reduce the likelihood of so-called false positives by also performing a Pap test on a woman who had a positive DNA test.
In an study involving 11,000 women between the ages of 25 and 34, researchers reduced the number of false DNA results and detected many more cases of dangerous pre-cancerous lesions when the genetics tests were combined with a Pap smear.
The author of the study, Guglielmo Ronco, of the Center for Cancer Prevention in Turin, says it's a lot easier to conduct a DNA test and a single Pap smear than yearly Pap tests.
"This is encouraging because we show that even within this age where infection is frequent you can use HPV and take advantage of that with appropriate strategy," said Ronco.
Ronco published his findings in the journal The Lancet Oncology.
Eduardo Franco, who wrote a commentary in the journal, says the DNA test is expensive, but adds once it becomes more widely available, especially in the West, the price will come down in countries where it is most needed.