News & Publications
New Cervical Cancer Screening Guidelines - Should Not Lessen the Importance of the Annual Exam
April 4, 2012
By Felix Martinez Jr, M.D.
The experts have weighed in and now have spoken in unison: “less is more.”
In March 2012, four major organizations - preventative, professional and governmental - jointly issued new guidelines for cervical cancer screening. Major changes are listed in Table 1 and are summarized below:
- Begin screening at age 21
- For women age 21-29, Pap testing only every three years
- For women over 30, combined testing (Pap & HPV test) with lengthening of testing interval to every five years for women who are Pap negative & HPV negative
- For women 65 and over with no history of HSIL in the past 10 years, cessation of Pap screening
The authors of the new guidelines reviewed thousands of trials and different types of studies performed all over the world1. The guidelines come from the United States Preventative Services Task Force (USPSTF) and a collaboration between the American Cancer Society (ACS), American Society of Colposcopy and Cervical Pathology (ASCCP), American Society for Clinical Pathology (ASCP) and the American Congress of Obstetrics and Gynecology (ACOG).
The organizations issuing these guidelines, for the first time, are now largely in agreement on the strategies for both screening and follow up.
It is evident that these changes in guidelines will not be the last in the progressive march of cervical cancer screening toward minimal testing over the longest possible interval.
The call for screening cutbacks is based on knowledge acquired over the last decade about the biology and epidemiology of HPV infection as well as the precancerous changes initiated by human papillomavirus.
The call for screening cutbacks is based on knowledge acquired over the last decade about the biology and epidemiology of HPV infection as well as the precancerous changes initiated by human papillomavirus.
Studies show that the death rate for cervical cancer is not affected by lengthening screening intervals, and the new guidelines aim to reduce the number of false positive tests and procedures which are deemed unnecessary by the experts.
Both the USPSTF and the consortium of medical groups led by the ACS continue to emphasize the importance of the Pap test. They recognize that efforts to promote Pap testing help reduce the number of women who develop cervical cancer because of poor access to healthcare. The experts, therefore, do not want to de-emphasize or devalue the Pap test, but want the Pap test and the HPV test to be used more effectively.
The new changes do not apply to women who are immune compromised or with HIV infection. Those having organ transplant or other immunosuppressive conditions or therapy are also excluded.
Co-testing - having both a Pap test and HPV test at the same time - was embraced by the USPSTF for the first time, calling it the “preferred” screening strategy for women 30-65. The USPSTF thereby acknowledges the principal that co-testing is effective because each test independently screens for slightly different things. In a concession to offering screening only with a Pap, the task force offers women ages 30-65 the option of having a Pap test alone every three years.
The presence of virus in women 30 and older may signal a persistent infection that increases the risk for cervical cancer. The high sensitivity of the HPV test in cervical cancer screening is a valuable part of co-testing.
All sets of new guidelines discourage use of HPV tests in women under the age of 30 because many in this age group will clear the infections on their own, without the need for medical intervention.
Previous guidelines for women under the age of 30 had recommended yearly testing for young women, starting within three years of their first sexual intercourse, but no later than age 21. Now, recommendations are that Pap testing begin at age 21, with Pap tests alone every three years for women age 21-29.
There were 11,270 cases and 4,070 deaths from cervical cancer in 2011. There have only been one to two cases of cervical cancer per 100,000 girls ages 15-19 over the past ten years.5 The low incidence in teenagers has convinced the experts that it is safe to wait until age 21 to screen.
Since cervical cancer is so rare under the age of 21, the experts have concluded that multiple sexual partners and/or early initiation of sexual activity doesn’t affect the incidence of cancer, and these former risk factors have been deemed irrelevant as long as screening begins at age 21.
The consortium also feels that it is safe to test women less often because cervical cancer progresses slowly and the screening “window” allows 10 - 20 years to catch precancerous changes.
For women who have had a total hysterectomy for a non-cancerous condition, testing can be eliminated if a woman has not had CIN 2-3+ on previous Pap testing.
Co-testing for women 30 and older is not a new recommendation and was part of the ASCCP Guidelines issued in 2009. One area of confusion in co-testing occurs when women are cytology negative but HPV positive.
Under the guidelines, there are two options for follow-up of these results:
Option #1) Repeat co-testing in one year. Women who re-test HPV-positive (or who have LSIL or HSIL) should undergo colposcopy. Women with normal or ASCUS cytology and who are HPV-negative should return to routine screening.
Option #2) Test immediately for HPV 16 and 18. Women who test positive for either of these viral types should undergo colposcopy
Women who test negative for both of these viral types should be co-tested in 12 months with management of results as outlined in Option #1.
Pap test or no Pap test, every woman needs a yearly medical exam for reasons vital to her health. Every set of new guidelines brings fear that women will visit their provider less often it they hear or read the phrase “in three to five years.” Therefore, practitioners have learned to emphasize the requisite need for an annual exam for “non-Pap” essentials such as cardiovascular screening, breast exam, cholesterol screening, colorectal screening, blood sugar irregularities, osteoporosis, thyroid disease and depression. For women under 21, blood pressure, height, weight, counseling on contraception and even counseling on domestic violence are important reasons for an annual visit.
Let’s not let any sort of guidelines lessen the importance of seeing a doctor once a year!
|
Table 1. Screening for Cervical Cancer Clinical Summary of U.S. Preventive Services Task Force Recommendations | ||||||
|---|---|---|---|---|---|---|
| Population | Women Age 21 - 65 | Women Age 30 - 65 | Women Younger than Age 21 | Women Older than Age 65 who have had Adequate Prior Screening and are Not High Risk | Women After Hysterectomy with removal of the Cervix with No History of High-grade Precancer or Cervical Cancer | Women Younger than Age 30 |
| Recommendation |
Screen with cytology (Pap smear) every 3 years. Grade: A |
Screen with cytology every 3 years or co-testing (cytology/HPV testing) every 5 years Grade: A |
Do not screen
Grade: D |
Do not screen Grade: D |
Do not screen Grade: D |
Do not screen with HPV testing (alone or with cytology) Grade: D |
| Risk Assessment | HPV infection is associated with nearly all cases of cervical cancer. Other factors that increase a woman's risk of cervical cancer include HIV infection, a compromised immune system, in utero exposure to diethylstilbestrol, and previous treatment of high-grade precancerous lesion or cervical cancer. | |||||
| Screening Tests and Interval |
Screening women age 21 to 65 years every 3 years with cytology provides a reasonable balance between benefits and harms. Screening with cytology more often than every 3 years confers little additional benefit, with large increases in harms. HPV testing combined with cytology (co-testing) every 5 years in women age 30 - 65 years offers a comparable balance of benefits and harms, and is therefore a reasonable alternative for women in this age group who would prefer to extend the screening interval. |
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| Timing of Screening | Screening women younger than age 21, regardless of sexual history, leads to more harms than benefits. Clinicians and patients should base the decision to end screening on whether the patient meets the criteria for adequate prior testing and appropriate follow up, per established guidelines. | |||||
| Interventions | Screening aims to identify high-grade precancerous cervical lesions to prevent development of cervical cancer and early-stage asymptomatic invasive cervical cancer. High grade lesions may be treated with ablative and excisional therapies, including cryotherapy, laser ablation, loop excision, and cold knife conization. Early stage cervical cancer may be treated with surgery (hysterectomy) or chemoradiation. | |||||
| Balance of Benefits & Harms | The benefits of screening with cytology every 3 years substantially outweigh the harms. | The benefits of screening with co-testing (cytology/HPV testing) every 5 years outweighs the harms. | The harms of screening earlier than age 21 outweigh the benefits. | The benefits of screening after age 65 do not outweigh the potential harms. | The harms of screening after hysterectomy outweigh the benefits, | The potential harms of screening with HPV testing (alone or with cytology) outweigh the potential benefits. |
| Other Relevant USPSTF Recommendations | The USPSTF has made recommendations on screening for breast cancer and ovarian cancer, as well as genetic risk assessment and BRCA mutation testing for breast and ovarian cancer susceptibility. These recommendations are available at: http://www.uspreventativeservicetaskforce.org. | |||||
| For a summary of the evidence systematically reviewed in making these recommendations, the full recommendation statement, and supporting documents, please go to http://www.uspreventiveservicestaskforce.org | ||||||
USPSTF Study Highlights6
- Women younger than 21 years should not be screened, and HPV testing should not be used for screening or management of atypical squamous cells of undetermined significance (ASC-US).
- Women 21 to 29 years old should be screened with use of cytology alone (not HPV testing) every three years. However, HPV testing may be used for secondary management decisions
- Women 21 to 29 years old who test positive for HPV with ASC-US or who have cytologic features of low-grade squamous intraepithelial lesion (LSIL) or more severe lesion should be treated according to ASCCP guidelines.
- Women 21 to 29 years old who have negative cytology results or HPV-negative ASC-US results should be rescreened with cytology in three years.
- Women 30 to 65 years old should preferably be screened with HPV testing and cytology every five years.
- Women 30 to 65 years old who have HPV-positive ASC-US or cytologic features of LSIL or more severe should be treated according to ASCCP guidelines.
- Women 30 to 65 years old who test positive for HPV with negative cytology results can have follow-up with co-testing in 12 months, or they can be tested for HPV 16 or HPV 16/18 genotypes. Those who have these genotypes should be referred for colposcopy.
- Women 30 to 65 years old who are co-test negative or have HPV-negative ASC-US results should be re-screened with co-testing in five years.
- Women 30 to 65 years old may also be screened with cytology alone every three years, and those who have HPV-positive ASC-US or cytologic features of LSIL or more severe should be treated according to ASCCP guidelines. Those who have negative cytology results or HPV-negative ASC-US should be re-screened with cytology in three years.
- Women older than 65 years should not be screened, provided prior screening was adequate and yielded negative results.
- Women older than 65 years with a history of CIN2 or a more severe diagnosis should continue routine screening for at least 20 years.
- After hysterectomy, women without a cervix and without a history of CIN2 or a more severe diagnosis in the past 20 years, or cervical cancer ever, should not be screened.
- Women vaccinated against HPV should follow the same age-specific recommendations as unvaccinated women.
References:
1 Screening for Cervical Cancer: U.S. Preventive Services Task Force Recommendation Statement, Moyer, VA, Ann Intern Med, 2012 Mar 14.
2 The Lancet Oncology, Volume 13, Issue 1, Pages 78 - 88, January 2012
3 CA: A Cancer Journal for Clinicians, Volume 62, Issue 2, pages 129–142, March/April 2012
4 New Guidelines Discourage Annual Pap Tests, The LA Times, March 14, 2012
5 U.S. Cancer Statistics Working Group. United States Cancer Statistics: 1999–2007 Incidence and Mortality Web-based Report. Atlanta (GA): Department of Health and Human Services, Centers for Disease Control and Prevention, and National Cancer Institute; 2010. Available at: http://www.cdc.gov/uscs
6 Nelson, R, Barklay L, ACS Issues Updated Cervical Cancer Screening Guidelines, CME/CE, Medscape, http://www.medscape.org/viewarticle/760690
