Thursday, October 18, 2007
New test for HPV
If women have latched on to anything from the onslaught of TV ads for the cervical cancer vaccine, and now for a special genetic test for human papillomavirus versus (HPV) , it's the idea that the chances of getting the disease depends a lot on the individual.
Consider, HPV causes most cervical cancers.
Of all the women in the U.S. with cervical cancer, 60 percent had never been screened, or hadn't been screened in the last 5 years, according to the American Cancer Society. That's why women should be diligent about getting their Pap tests. It's the gold standard for detecting cell changes in the cervix that could be caused by HPV.
But now, there's fresh interest in a different kind of test - a DNA test for HPV, a swab done during a regular pelvic exam, that its supporters say is better than the Pap, and may even muscle it out as the cervical cancer screening method of choice.
So, many women will ask - "Do I need an HPV test?"
The New England Journal of Medicine features a pair of studies extolling its virtues.
One, a Canadian study looking at more than 10,000 women, found the HPV test correctly found 95 percent of the lesions that could develop into cervical cancers; while the Pap test found only 55 percent.
Most women would take those odds, but it's not that simple.
First, the HPV test is only for women 30 years old and older. Think of it like this - virtually everybody who has sex is exposed to HPV, but the vast majority of HPV infections just flush out of a woman's body. So the test is only used on women 30 and older to reduce the number of transient infections.
And what exactly does it mean if you test positive for HPV? The HPV test has shown to be more sensitive than the Pap, but it's also less specific - so it can have a slightly higher false positive rate.
So a positive result could mean you need a follow-up test 6 to 12 months later. If that test is positive the HPV could have been hanging around awhile, putting you at risk for cancer.
Or it could mean nothing at all. There's concern too many people taking the test would test positive for HPV and get unnecessary treatment as a result.
Another issue - and not a small one - is that the HPV test isn't widely available and it is not always covered by insurance.
For now, the American Cancer Society says women should be screened using the Pap test, or Pap plus the HPV test if she chooses, because the HPV test does offer added benefits over the Pap alone. At this time, women can only get an HPV test along with a Pap test; it's not FDA approved as a primary screening test.
A benefit of double screening if both the HPV and a Pap test are negative is that doctors say you won't need another screen for three years, so it may save you a trip to the OB/GYN.
But, will HPV testing supplant Pap tests? Dr. Brian Slomovitz, Assistant Professor in the Division of Gynecologic Oncology in the Department of Obstetrics and Gynecology, New York Presbyterian/Weill Cornell believes we're in the cusp of a "revolution in cervical cancer screening" as we know it.
The American Cancer Society is quick to point out that questions remain.
The most recent research comparing these screening tests appears in the October 18 issue of the New England Journal of Medicine.
Will you seek out the new HPV test in addition to a Pap test on your next doctor's visit? We'd like to hear from you.
ABOUT THE BLOGGet a behind-the-scenes look at the latest stories from CNN's chief medical correspondent, Dr. Sanjay Gupta, and the CNN Medical Unit producers. They'll share news and views on health and medical trends -- info that will help you take better care of yourself and the people you love.
PREVIOUS POSTS• The road to recovery for a footballer
• Tips for taking OTC pain meds
• Giving autism a voice
• Fighting addiction
• Mind body relationship and stress
• Fighting presenteeism
• Are Tasers safe?
• Kids and Drinking Revisited
• Concussions and girls
• Panic attack may lead to another kind of attack