With apologies to Mark Twain, reports of the death of the Pap smear are premature.
Yes, new research suggests a test for the HPV virus that causes cervical cancer may replace the old-fashioned Pap one day as that cancer's primary screening tool. But even enthusiasts say it will take years of additional research to make such a big switch.
For now, a new trend is the Pap-plus -- both a Pap and an HPV test -- to improve screening accuracy. But government researchers issued a caution this month: Nearly one in 10 women over age 30 who get the combo test learns they have HPV even though their Paps show no cancer or even precancerous cells. They'll need repeat checkups, and maybe more in-depth testing, to tease out who's really at risk.
What makes the issue confusing: Women's bodies very often clear an HPV infection on their own, without lasting harm, but it can take a year. The younger the woman, the more likely that HPV is going to be transient.
"One HPV test does not tell you very much. Two consecutive HPV tests are what you need," said Debbie Saslow of the American Cancer Society.
Cervical cancer will strike just over 11,000 U.S. women this year and kill 3,870, the cancer society predicts. Paps are credited for cutting death rates in half since the 1970s, because they can spot precancerous cells in time to remove them and prevent invasive cancer.
HPV, or human papillomavirus, is a common sexually transmitted disease. Some of HPV's dozens of strains can cause cervical cancer if a woman remains infected for a long time. The HPV test is designed to detect most of the worst strains.
A positive HPV test detects that the virus is present, but can't measure duration of infection or actual abnormalities on the cervix, which require more in-depth follow-up testing.
The HPV test's extra sensitivity, casting a wider net for who's at risk, is precisely what has researchers around the world furiously studying it as a potential replacement for the Pap. However all this research turns out, cancer groups for now stand by their guidelines:
•Women under 30 should get a Pap alone. If it's is inconclusive, HPV testing can rule out who needs further examination. A first test should be three years after starting sexual intercourse or at age 21.
•Women over 30 have the option of a Pap followed by an HPV test, or a simultaneous Pap-HPV combo. If both are negative, women can wait three years to be tested again.
•Women who don't get the HPV test still can wait three years between Paps, if they've had three consecutive clear Paps.
•Anyone who's received the new HPV vaccine still must follow guidelines for their age group. That's because the vaccine prevents some but not all HPV strains, and some teens or young women may have been infected already before they were vaccinated.
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