“Astonishment fatigue.” That phenomenon may be responsible for clinicians’ muted reaction to new ACOG guidelines on cervical cancer screening, which were released late last year. 1 Through a coincidence of timing, the new guidelines hit the airwaves just after the U. S. Preventive Services Task Force announced controversial changes to its recommendations on mammography. As a result, the cervical cytology guidelines seemed to dissolve into the stratosphere.
Or, perhaps, the cervical cancer screening guidelines slipped by with little fanfare because they were soundly based in evidence and, therefore, widely accepted among ObGyns. Even if that is the case, the medical community may not be familiar with the specific data behind the guideline changes. In this article, I discuss the evidence driving all major changes to the guidelines based on Level-A evidence. Changes based on Level-B or -C evidence are listed in TABLE 1 .
Hold off on cervical cancer screening until the patient is 21 years old
Screening before age 21 should be avoided because it may lead to unnecessary and harmful evaluation and treatment in women at very low risk of cancer.1
How different is this from the 2003 ACOG recommendation to begin screening within 3 years of first intercourse or at age 21, whichever comes first?
Very, very different. In fact, it is the most dramatic change in the 2009 screening recommendations.
It is even more striking in comparison with ACOG’s earlier recommendation—which prevailed from the late 1970s through 2002—to begin cervical screening at age 18 or at the onset of intercourse, whichever comes first.
The median age of first intercourse in the United States is 16 years. Until this latest change in guidelines, most young women began cervical screening during adolescence.
What’s wrong with screening adolescents? Don’t they acquire human papillomavirus (HPV)? (Yes.) And once they do, aren’t they at risk of cervical cancer? (Yes.)
Several variables support the delay of screening to age 21:
- the transience of most HPV infections
- the typically long natural history of carcinogenesis in the few young women in whom HPV might persist
- the adverse consequences of over-screening and over-management of adolescents who have cervical intraepithelial neoplasia (CIN).
Let’s look more closely at these variables.
TABLE 1
Other ACOG cervical disease guidelines are based on Level-B and Level-C evidence*
| Recommendation | Level of evidence | Comment |
|---|---|---|
| Test sexually active adolescents (i.e., females 21 years or younger) for sexually transmitted infection, and counsel them about safe sexual practices and contraception | B | These measures can be carried out without cervical cytology and, in the asymptomatic patient, without the introduction of a speculum |
| It is reasonable to discontinue cervical cancer screening in any woman 65 to 70 years old who has had three or more consecutive negative Pap tests and no abnormal tests in the past 10 years | B | |
| Continue annual screening for at least 20 years in any woman who has been treated for CIN 2, CIN 3, or cancer. This population remains at risk of persistent or recurrent disease for at least 20 years after treatment and after initial posttreatment surveillance | B | |
| Continue to screen any woman who has had a total hysterectomy if she has a history of CIN 2 or CIN 3 or if a negative history cannot be documented. This screening should continue even after initial post-treatment surveillance | B | Although the screening interval may ultimately be extended, we lack reliable data to support or refute the discontinuation of screening in this population |
| Inform the patient that annual gynecologic examination may still be appropriate even if cervical cytology is not assessed at each visit | C | |
| Screen any woman who has been immunized against HPV 16 and 18 as though she has not been immunized | C | |
| * Level-B recommendations are based on limited and inconsistent scientific evidence. Level-C recommendations are based primarily on consensus and expert opinion. | ||
HPV is common but usually resolves on its own
It’s common for young women to acquire HPV shortly after they become sexually active, but their immune system clears most infections within 1 or 2 years without the virus producing neoplastic changes.1
HPV detection peaks in the late teens and early 20s, when approximately 25% of women test positive for the virus, resulting in high rates of low-grade squamous intraepithelial lesions (LSIL) and HPV-positive, atypical squamous cells of undetermined significance (ASC-US).2 These findings are mostly transient.2