As technology changes, so does the way in which people are screened and treated for STDs. Cervical cancer screening guidelines, in particular, may end up changing in the near future, not only because of improvements in technology but because of the availability of an HPV vaccine.
The vast majority of cervical cancer cases are caused by HPV; however, HPV testing is not part of the screening regimen for most women. It used to be that this made sense, since HPV testing wasn't widely available, but this is changing. Still, since HPV tests can't check for all the possible strains of HPV that could cause cervical cancer, the Pap smear will always continue to play a role.
Until recently, the American Cancer Society screening guidelines stated that young women should start getting Pap smears at age 21 or within three years of starting sexual activity - whichever is sooner. They should get tested once a year with the regular Pap smear, or once every 2 years with the liquid Pap until the age of 30. For these women, the HPV test is only used when the results of the Pap smear are uncertain.
Once a woman reaches the age of 30, if she's otherwise low risk and has had 2 to 3 normal Pap smears in a row, she can switch to being tested either every 2 years, or every three years if she is tested using the HPV DNA test as well. Women over the age of 70 with no risk factors and 10 years of negative Pap tests may choose to forgo testing altogether.
NEW: In the fall of 2009, the American College of Obstetricians and Gynecologists broke ranks with its fellows and changed their guidelines for cervical cancer screening. Because there are so few cases of invasive cervical cancer among young women, and there is a risk of overtreatment, the ACOG guidelines now say that even sexually active young women should not be given a Pap smear before the age of 21. Then, starting at age 21, women should be screened every other year instead of every year, and they should be screened only once every three years after the age of 30 if a they have had three normal Pap tests in a row.
Now that the HPV DNA test has become more widely available, some scientists are recommending changes in the screening guidelines to utilize its predictive powers. One recent study suggested that it might be cost-effective to switch to HPV testing with Pap smear confirmation for women over 30, although they found that for younger women, Pap smears followed by an HPV test confirmation still made more sense.
As time goes on, and more and more women are vaccinated against the high risk strains of HPV, HPV DNA testing will become less and less useful. For right now, however, it could be an important screening tool, especially since the vaccine is unavailable to women over 30 - the very women for whom DNA testing may be most valuable.
Chustecka, Z. "Changes in Cervical Cancer Screening Guidelines Could be Cost-Effective." Medscape Medical News. (Accessed 3/16/08)
American Cancer Society Screening Guidelines. (Accessed 3/16/08)