Since the Pap smear was introduced more than half a century ago, the death rate from cervical cancer has plummeted. The question now is not whether women should be screened for the highly treatable disease, but how often and with what test. Fortunately, new guidelines make that decision easier.

"Cervical cancer screening has been fantastically successful because we've had such a tremendous impact on mortality over the last 50 years," says Dr. Diane Solomon, a senior investigator in the breast and gynecologic cancer research group at the National Cancer Institute. "Cervical cancer is virtually 100 percent curable when it's in the precancerous stage."

Catching it early is critical; more than half of the deaths from this type of cancer occur in women who weren't adequately screened.

An estimated 12,200 new cases will be diagnosed in 2003, and approximately 4,100 women will die of the disease, according to the U.S. Centers for Disease Control and Prevention.

Today, women have more screening options than ever. That means more choices need to be made and what better time to start making them than in January, which is Cervical Health Awareness Month.

Cervical cancer is caused by the ubiquitous human papillomavirus (HPV). At some point in time, the majority of women will have the virus, which is sexually transmitted. However, most will get rid of it quietly and painlessly, often without realizing they're infected, experts say.

"Most women never know they have it and don't need to be concerned they have it," says Debbie Saslow, director of breast and gynecologic cancer at the American Cancer Society.

In the extreme minority of cases, however, the virus progresses to cancer. "Only a very small number of HPV infections that are persistent become a risk for cervical cancer," Solomon says. Because it probably takes decades for an HPV infection to become cancer, screening tests have ample time to stop the disease in its tracks.

A number of organizations have issued guidelines for cervical cancer screening, guidelines that were recently confirmed by a study in the New England Journal of Medicine. The guidelines recommend women under 30 should have annual Pap smears. Those over 30 who have had three normal (or negative) Pap tests in a row can extend the interval between screenings to three years.

"Cervical cancer is so slow-growing that getting screened every year [for low-risk women] is really overkill," Saslow says. Women who get screened too often can end up with abnormal results that are medically meaningless but can cause huge amounts of anxiety and cost money.Women should start screenings three years after becoming sexually active or when they turn 21. Previous guidelines had recommended starting at age 18, which is now considered too early.Those 65 and older who have been screened and have been getting normal Pap results can stop if they want.

It's also not necessary to get screened if you had your cervix removed as part of a hysterectomy. Before you stop getting tested, however, make sure your cervix really was removed, as it is in 99 percent of these procedures. The new recommendations don't specify that women must have a traditional Pap test. Although the Pap is "still a good test," Solomon says, there are now a range of choices.

The Pap smear, which is done as part of a routine pelvic exam, involves using a Q-tip or similar tool to take a sample from the cervix (the neck of the uterus and easily accessible through the vagina). The sample is smeared on a slide, then sent to a lab for analysis.

"The Pap has a high failure rate, but that hasn't been a big problem because cervical cancer is so slow you can get it the next year," Saslow says. "But people are still not comfortable with the fact that the Pap test misses a lot."

The newer liquid-based Pap test takes the sample in the same way but, instead of scraping it on a slide, dips it into liquid. The advantage of this test, Saslow says, is like shaking up a box of Raisin Bran. If the suspicious cells are the raisins, it's better to shake the box up. The liquid provides a more purified sample, a more representative sample and also eliminates mucus, blood and other obfuscating elements. On the downside: the cost is double and the sensitivity is increased, meaning the test may flag things that really aren't a cause for concern.

The HPV test looks specifically for the HPV virus, as opposed to the abnormal cells that are targeted in the above two tests. This means that women under the age of 30, most of whom will have the virus, should not take the test, health experts say.

"In young women, the cost-benefit balance of using the HPV test to augment screening is not beneficial," Solomon says. "Too many women are HPV-positive and the risk of cancer is so low, it's more an issue of overtreatment."

Even for those over 30, many more women are going to test positive than are going to develop cancer. The HPV test is done with a Pap test so if the Pap is normal and the HPV is positive, women will have to wait a year before deciding if they need to take another step. On the other hand, if you test negative on the HPV and the Pap tests, your odds of developing cancer are virtually nil.

"If you get a negative HPV test, your chance of getting cervical cancer in the next few years is almost zero," Saslow says. "The reassurance is extremely high, but the problem is a lot of people are going to test positive and they don't need to be that worried."

By Amanda Gardner
HealthDay Reporter

NOTE Due to the fact that Pap smears can identify other illnesses, such as vaginal cancer, some suggest a wiser course of action is to continue to have a Pap smear even if you have had a hysterectomy and your cervix was removed.