As of Thursday, April 25, 2013
DEAR DOCTOR K: I’m a woman in my 30s, and I’ve never had an abnormal Pap test. Do I still need one every year?
DEAR READER: The answer used to be yes. This helped ensure that you had regular Pap tests to screen for cervical cancer. But new guidelines recommend less frequent Pap tests for younger women, and no Pap tests for many older women.
The new guidelines, issued in 2012, revised the recommendations for cervical cancer screening. They suggest that women ages 21 to 65 have a Pap test every three years or, for women ages 30 to 65 who want to lengthen the screening interval, have a combination Pap test and human papillomavirus (HPV) test only once every five years. (Most cervical cancers are caused by specific types of HPV, a sexually transmitted virus.)
In addition, most women ages 65 and older and women who have had a hysterectomy (and no longer have a cervix) do not need to have Pap tests. The exceptions are women with a history of precancerous cells, cervical cancer or abnormal Pap/HPV tests.
The new recommendations stem from a better understanding of how cervical cancer develops. It doesn’t develop very rapidly. Rather, there are clear precancerous stages that take years to progress.
What’s the downside of an annual Pap test? For young women in particular, frequent Pap tests can lead to false positive results (the test result suggests a possible cancer, but there really is no cancer). That false positive result can lead to unnecessary worry and anxiety. It also can lead to further, and invasive, diagnostic tests such as a colposcopy and biopsy of the cervix. These invasive diagnostic tests, in turn, can cause vaginal bleeding, infections and pain.
And, less often, the Pap test and HPV test can produce false negative results (the test result is normal, but there really is a cancer).
For cervical cancer and many other cancers, our screening tests are not perfect. With a perfect test, every time it came back abnormal there would really be a cancer — and that would justify additional invasive diagnostic tests. And with a perfect test, every time it came back normal you could know for sure that you were free of that cancer.
If there were a perfect test, of course you would want to have it periodically. But if the test were imperfect, and could cause you complications, you’d want to have it when it was more likely to benefit you than to harm you.
So recommendations as to how often a woman should have a Pap test are based on what studies show are the risks of a false positive or false negative result, and how likely cervical cancer is in the person having the test. For example, cervical cancer is less common in young women than in women in their late 50s.
The bottom line: You still need the Pap (and the HPV) test, but not as often as you did in the past.
(Dr. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.)
Dr. Anthony L. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.