WEDNESDAY, May 18 (HealthDay News) -- Women 30 and older who have good results from each of the two cervical cancer tests available today can safely wait three years for their next screening instead of just one year, according to new research.

The finding is not likely be controversial, said Dr. Charles Capen, chief of gynecology/oncology at Scott & White Healthcare in Temple, Texas, given that most current guidelines already recommend that women 30 and over who are otherwise healthy be screened with both a Pap smear and a test for a virus linked to cervical cancer every three years as long as the initial tests are both negative.

Unlike some cancers, cervical cancer is usually slow-growing, and it is curable if detected early, according to the U.S. National Cancer Institute.

"This [new research] confirms the latest guidelines," agreed Dr. Therese Bevers, medical director of the Cancer Prevention Center at the University of Texas M.D. Anderson Cancer Center in Houston. "That is fabulous as it can give clinicians and women everywhere a lot of reassurance."

Hopefully, it will also spur more doctors to actually follow these guidelines, added Bevers, as recent research has revealed that most doctors are giving the Pap test more often than recommended -- i.e., once a year.

The study findings will be presented at the annual meeting of the American Society of Clinical Oncology being held in June in Chicago. The results were released early Wednesday during a teleconference.

Cervical cancer risk can be assessed by two different tests: the traditional Pap smear, which searches for abnormalities in cervical cells, and a newer test that can detect DNA of the virus that causes most cases of cervical cancer: human papillomavirus, or HPV. That screening is referred to as the HPV test.

The new study involved more than 330,000 women enrolled in a large northern California health plan who were undergoing both types of tests between 2003 and 2005 and who were followed for five years after being tested.

The estimated five-year risk for developing cervical cancer was 7.5 per 100,000 women in those who had normal Pap smears, versus a much lower 3.8 per 100,000 for women who were negative on the HPV test.

When the two tests were performed together with both yielding negative results, the estimated risk was 3.2 per 100,000 women, meaning that the HPV test alone is almost as good as the two combined.

"A single negative HPV test [predicted] an extremely low cancer risk for women [which] was not appreciably lowered by having a normal Pap test," said lead author Hormuzd Katki, principal investigator in the Division of Cancer Epidemiology and Genetics at the U.S. National Cancer Institute.

That means that women who test negative on the HPV test alone might be able to extend their screening intervals to three years with no adverse consequences, Katki added.

"This generates the question, should HPV testing become the standard at some point," Bevers said.

This might be especially important in developing countries that often don't have the capability to interpret Pap tests, Bevers said.

"HPV testing is much easier," she added. "It's kind of like doing a pregnancy test at home. It's positive or negative."

There is still a role, however, for the Pap test -- to follow up a positive HPV test, said Katki. "The Pap test can identify women who have more immediate disease," he said.

"But many women equate a Pap smear with their annual gynecological exam and one of the arguments against three-year screening intervals is that women would no longer see their doctor every year and get other necessary tests, such as blood pressure, cholesterol and testing for sexually transmitted infections," Capen said.

Capen, though, thinks that won't happen. "Young women may be on the pill or they may be pregnant, so hopefully they will still get the medical care they need," he said.

Since the study findings are to be presented at a medical meeting, they should be considered preliminary until published in a peer-reviewed journal.

More information

There's more on cervical cancer screening at the U.S. Centers for Disease Control and Prevention.