Young women should have their first Pap test no sooner than age 21,
regardless of when they become sexually active, say new guidelines from
the American College of Obstetricians and Gynecologists. Earlier
screening for cervical cancer may lead to unnecessary and possibly
harmful treatments for an increasingly rare cancer, according to ACOG,
the leading U.S. professional organization for obstetricians and
gynecologists.
After age 21, women should have a Pap test every
two years, instead of every year. At age 30, if a woman has no history
of cervical cancer and has had three normal Pap tests in a row, she can
be screened every three years, rather than every two to three years.
(Women with certain risk factors, such as those who are HIV positive or
who have a suppressed immune system, may need to be screened more
often.)
However, annual pelvic exams -- which are necessary for
performing a Pap test -- won't necessarily be going away. ACOG says it
may still be appropriate for women to visit their doctor annually for a
pelvic exam, even if a Pap test isn't performed. And sexually active
adolescents shouldn't wait until age 21 to see a gynecologist for the
first time. (Such visits don't necessarily have to include a pelvic
exam.)
The guidelines were published this week in the journal Obstetrics & Gynecology.
ACOG
had previously recommended that women receive their first Pap test
three years after having sex for the first time, or no later than age
21, with annual checkups after that.
Why the change? Rates of cervical cancer,
which is caused by the sexually transmitted human papillomavirus, have
declined by 50 percent since the 1970s. Cervical cancer is now
extremely rare, especially among women under the age of 30, the group
most affected by the new guidelines. On average, just 14 cases occur
nationwide in women between the ages of 15 and 19 each year, according
to data from the Centers for Disease Control and Prevention. Among
women ages 20 to 24, an average of 123 cases occur.
"The risk of
invasive cancer is so exceedingly rare in this age group that to start
screening at age 21 will still pick up the overwhelming majority of
cases," says Dr. Alan Waxman, a professor of ob-gyn at the University
of New Mexico School of Medicine, in Albuquerque, who led the
preparation of the document spelling out the recommendations. "The
incidence of cervical cancer in 15- to 19-year-olds has been reported
at 1 to 2 per million girls. That's a lot of unnecessary pelvic exams
and unnecessary potential treatments that can be avoided."
The cervical cancer rate will probably drop even further due to newer vaccines like Gardasil, which are now approved for HPV
prevention in girls and women ages 9 to 26. However, ACOG says the
vaccines won't affect cervical cancer rates for 15 to 20 years, so they
did not play a role in the new cervical cancer screening guidelines.
Such vaccines don't protect against all types of HPV that can cause
cancer, so Pap tests are still necessary.
About
half of all people are infected with HPV at some point in their
lifetime, although the infection often goes away on its own. (Only in
some cases does the virus damage cervical cells, causing abnormalities
that can be picked up on a Pap test.)
Studies that ACOG consulted also show
that screening older women every two to three years is nearly as
effective as screening annually. And for women who've had healthy Pap
tests for years, screening could probably be stopped around ages 65 to
70.
Dr. Mark Einstein, an associate professor of gynecologic
oncology at Montefiore Medical Center, in the Bronx, New York, and a
spokesman for the Society of Gynecologic Oncology, says the new
guidelines are a "data-driven fine-tuning," not a major overhaul.
"It's important for patients to realize that the science behind the guidelines is strong," Einstein adds.
ACOG's
revisions reflect a trend toward a more conservative approach to
managing the cervical abnormalities that sometimes lead to cancer.
Cervical
lesions are common, especially among adolescents. About 1 in 5 Pap
tests in that age group will turn up an abnormality, but the vast
majority of low-grade cervical lesions -- up to 90 percent -- will get
better on their own within three years. Among older women, the rates
are lower, but low-grade lesions still rarely progress to the
precancerous stage.
Moreover, a series of studies in recent
years suggests that women who have cervical lesions surgically removed
or burned away with a laser may be at a higher risk of giving birth to
a premature or underweight baby. As a result, ACOG and other
organizations now recommend monitoring the condition rather than
immediately treating it when some types of lesions are found.
Scaling
back the schedule for Pap tests will minimize unnecessary and
potentially harmful procedures, the guidelines say. Although they also
cite the expense of screening and the anxiety and "emotional impact"
caused by abnormal Pap tests, "the risk of treatment was the driving
factor" behind the changes, says Waxman.
ACOG's recommendations
come less than a week after the U.S. Preventive Services Task Force
(USPSTF), an independent panel of experts that advises the federal
government on preventive care, released new guidelines for breast
cancer screening. The task force recommended that women begin
mammograms at age 50, not 40, and decrease the frequency thereafter.
Both
the mammography and Pap test guidelines are part of a broader,
evidence-based shift toward less screening, says Dr. Karen Soren, the
director of adolescent health services at Columbia University Medical
Center, in New York City.
"We always used to feel that the more
screens you get, the better. And I think there's a new philosophy,"
says Soren, who has studied Pap tests in adolescents. "The whole
medical community in general is saying, 'Perhaps we're overscreening.'
And that relates to mammography as well."
By changing its guidelines, ACOG is breaking ranks with the other main authorities on cervical cancer. The American Cancer Society and the USPSTF both recommend that women get their first Pap test within three years of having sex, or at age 21.
The
ACS recommends that women ages 21 to 30 be tested every one or two
years, depending on whether a conventional or liquid-based Pap test is
used. Women over 30 with three consecutive normal Pap tests can be
screened every two to three years, again depending on which tests are
used. (ACOG guidelines do not distinguish between the different types
of testing.)
The USPSTF's mammogram guidelines, which
deviated from those of the ACS, caused an uproar and have sown
confusion among women, but experts agree that ACOG's recommendations
aren't likely to have the same effect.
In fact, the ACOG
committee that assembled the guidelines believes it will help eliminate
confusion and simplify care. "Now age 21 is there as a landmark point
in a young woman's lifetime: 'Gee, I'm 21, now it's time to get my Pap
test,'" says Waxman.
The hope, he says, is that the ACS and the
USPSTF will head in the same direction with their own recommendations.
"It's very frustrating when you have three major professional
organizations saying three different things," Waxman says.
Setting
a woman's first Pap test at age 21 is clearer than pegging it to sexual
activity, says Soren. "The recommendations have been changing and
evolving, and people have been slow to catch on," she says. "Patients
have been asking for different things. I think the fact that there are
concrete guidelines now is actually better."
Fred Wyand, a
spokesman for the American Social Health Association, a nonprofit
organization that raises awareness about HPV and cervical cancer
prevention, downplayed the potential for confusion among the public or
health-care providers. The debate over the schedule for Pap tests is
"not new," says Wyand. "The guidelines are new, but the discussion that
preceded it dates back years. So I don't think anybody's going to be
caught off guard."
Experts stress that annual pelvic exams may
still be appropriate even though Pap tests will be performed less
frequently. And, most importantly, women who have received the HPV
vaccine need to stick to the same screening schedule as everyone else.
"It
is number one on our list to make sure that patients know that
vaccination doesn't replace screening," says Einstein. "We're not ready
to be making separate guidelines for vaccinated and non-vaccinated
patients, and we won't be ready to do so for some time."
Copyright Health Magazine 2009