DNA Test Beats Pap Smear in Cervical Cancer Detection, Study Finds

In addition, the HPV test is sensitive enough that women may be able to go several years between screening appointments.

"We have data from other studies that the protection from a negative HPV test for three to five years is probably about the same as a negative pap smear for one year," added Mayrand. "I am confident that the interval will be able to be lengthened to three or maybe even five years."

More False Alarms

However, DNA testing for HPV was found to have a slightly worse specificity than Pap smears. While the Pap tests only gave false positives 3 percent of the time, the DNA tests yielded a 6 percent false positive rate.

The concern is the additional false positives could force more women to have further medical workup or procedures.

In an accompanying editorial in the New England Journal of Medicine, Dr. Carolyn Runowicz, director of the Neag Comprehensive Cancer Center at the University of Connecticut in Farmington, pointed out, "Improving sensitivity will, by definition, increase the number of false positives and sacrifice specificity."

Mayrand admitted that the DNA test followed this pattern as well. "For any test, specificity and sensitivity go together -- but inversely," she said. "The more sensitive, the less specific."

But she added that the trade-off may be more positive than negative for the women involved.

"The thing that's really interesting is that we found a large gain in sensitivity -- about 40 percent, but only a small drop in specificity -- only 3 percent," she said. "But it is a shortcoming -- we'd all like a perfect test."

Not For Everyone

Before women begin inundating their doctors with questions about the DNA test for HPV, it is important to note that it is not designed to be used by itself for women under 30 -- a time when many women will have asymptomatic infection with HPV.

"In women under 30, HPV infections are frequent," said Mayrand. "Most acquire HPV in the first few years after their sexual debut. But most of those infections will clear on their own and go away. We are happy to not pick those up."

But Dillner thinks that eventually, HPV testing could replace Pap smear testing -- at least for women over 30.

"I think that having HPV as screening instead of Pap is quite likely to happen eventually," Dillner said. "It will be unlikely we screen with just HPV below 30 years of age, but from 35 years and up it is highly likely that we will see at least some countries using HPV screening -- and at quite long intervals."

Maynard agreed. "I would say that in a few years she'll probably be able to have a better test less often; that's the key message," she said. "Instead of a mediocre test every year, let's have a great test every five years."

And patient Curlutu agreed that such a change would be a welcome one.

"It might be nice to go longer between visits," she said. "And given the tradeoff, I think I would like to have the test done -- even if it picks up on something that might not be serious ... I'd rather be safe than sorry."

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