Patient education: Cervical cancer screening (Beyond the Basics)
- Sarah Feldman, MD, MPH
Sarah Feldman, MD, MPH
- Associate Professor
- Harvard Medical School
- Annekathryn Goodman, MD
Annekathryn Goodman, MD
- Obstetrics, Gynecology, Reproductive Biology
- Harvard Medical School
- Division of Gynecologic Oncology
- Massachusetts General Hospital
- MGH Global Disaster Response
- Jeffrey F Peipert, MD, PhD
Jeffrey F Peipert, MD, PhD
- Clarence E. Ehrlich Professor and Chair
- Department of Obstetrics & Gynecology
- Indiana University School of Medicine
- Section Editors
- Joann G Elmore, MD, MPH
Joann G Elmore, MD, MPH
- Editor-in-Chief — Primary Care (Adult)
- Section Editor — General Medicine
- Professor of Medicine, David Geffen School of Medicine at UCLA
- Barbara Goff, MD
Barbara Goff, MD
- Section Editor — Gynecologic Oncology
- Department Chair, Gynecologic Oncology
- University of Washington Medical Center
CERVICAL CANCER SCREENING OVERVIEW
The Papanicolaou smear (Pap test) and testing for human papillomavirus (HPV) are the tests used to screen women for cervical precancer or cancer.
Cervical cancer screening tests can find cervical cancer and precancer in the early stages when it can be treated and thus may reduce the number of deaths from cervical cancer. This article reviews tests used to screen for cervical cancer and a description of both normal and abnormal Pap test results.
The evaluation and treatment of abnormal Pap tests are discussed separately. (See "Patient education: Follow-up of low-grade abnormal Pap tests (Beyond the Basics)" and "Patient education: Follow-up of high-grade abnormal Pap tests (Beyond the Basics)" and "Patient education: Management of a cervical biopsy with precancerous cells (Beyond the Basics)".)
CERVICAL CANCER RISK FACTORS
The most important risk factor for cervical cancer is infection with the human papillomavirus (HPV). There are over 100 different types of HPV; however, most types of HPV do not cause cancer. At least 80 percent of women are exposed to the HPV virus during their lifetime. Most of the time, the body's immune system gets rid of the virus before it does harm.
Researchers have labeled the HPV types as being high or low risk for causing cervical cancer.
●Low-risk HPV types – HPV types 6 and 11 can cause genital warts and are low-risk types because they rarely cause cervical cancer. (See "Patient education: Genital warts in women (Beyond the Basics)".)
●High-risk HPV types – High-risk HPV types may cause cervical cancer in some women. Although most women who are infected with the high-risk HPV types do not develop cervical cancer, women who test positive for high-risk HPV over many years are at a higher risk of cervical cancer. HPV types 16 and 18 are two of the high-risk types.
HPV is spread by direct skin-to-skin contact, including sexual intercourse, oral sex, anal sex, or any other contact involving the genital area (eg, hand-to-genital contact). It is not possible to become infected with HPV by touching an object, such as a toilet seat. Most people who are infected with HPV have no signs or symptoms. Most HPV infections are temporary and resolve within two years. When the virus persists (in 10 to 20 percent of cases), there is a chance of developing cervical precancer or cancer. However, it usually takes many years for HPV infection to cause cervical cancer.
Since HPV is transmitted by sexual contact, having multiple sexual partners is associated with an increased risk for cervical cancer. Condoms provide only partial protection. Smoking can increase the risk of cervical cancer up to fourfold, as does having a condition or taking a medicine that weakens the immune system.
A vaccine to help prevent infection with some high-risk types of HPV is recommended for girls or women between the ages of 9 and 26 years and for boys or men between the ages of 9 and 21 years but can be given up to 26 years of age. Smoking cessation is recommended for those who smoke. (See "Patient education: Human papillomavirus (HPV) vaccine (Beyond the Basics)" and "Patient education: Quitting smoking (Beyond the Basics)".)
CERVICAL CANCER SCREENING TESTS
There are several ways to screen for cervical cancer. The traditional screening test is called a Papanicolaou smear (Pap test).
To perform a Pap test, a doctor or other health care provider will perform a pelvic exam and use a small brush or spatula to collect cells from the cervix. The cells are smeared on a glass slide (called a traditional Pap smear) or added to a preservative fluid (called liquid-based, thin layer testing). Studies that have compared the traditional Pap smear with liquid-based cytology do not prove one test to be more accurate than another.
HPV test — An HPV test can be done along with a Pap test or as a separate test. Like a Pap test, the HPV test is done during a pelvic exam, using a small brush to collect a sample from the cervix. HPV tests do not test for all different types of HPV. They test for the strains of HPV that are the highest risk for causing cervical cancer.
WHO SHOULD BE SCREENED FOR CERVICAL CANCER?
Younger women — In the United States, it is recommended that cervical cancer screening start at age 21; some other countries suggest that screening begin at age 25. Cervical cancer is very rare in younger women. Screening before age 21 in girls and women who are sexually active is not recommended because of the very high risk of false-positive results (that is, do not indicate a precancerous condition) because many HPV infections in this group are temporary. There is concern that procedures done to follow-up on these results may impair a young woman’s future fertility.
Even if you have had a vaccine for human papillomavirus (HPV), you will still need cervical cancer screening. (See "Patient education: Human papillomavirus (HPV) vaccine (Beyond the Basics)".)
Older women — Most experts feel that many women who are 65 years or older can stop having cervical cancer screening, though it depends on their risk factors.
For example, you may need to continue having cervical cancer screening beyond the age of 65 if:
●You smoke or used to smoke.
●You have ever had an abnormal Pap or HPV test or been treated for cervical dysplasia (abnormal cells that can lead to cancer).
●You have a new sexual partner since your last Pap test.
●You were exposed to diethylstilbestrol (DES) where you were in the womb – DES is a drug that was given to many women before 1981 to prevent pregnancy complications. Women who were exposed while in the womb have an increased risk of certain health problems, including cervical cancer, later in life.
If you are 65 or older and do not have any of the above risk factors, most experts feel that you can stop having cervical cancer screening if:
●You have had screening tests on a regular basis in the past
●You have had at least three normal Papanicolaou smears (Pap tests) in a row or two tests with combination Pap and HPV test over the past 10 years, with the most recent within the past five years
After hysterectomy — Women who have had a total hysterectomy (your uterus and cervix were removed) do not need a Pap test, unless:
●The hysterectomy did not remove your cervix (eg, if the hysterectomy was "subtotal")
●Your hysterectomy was done because of cervical cancer or precancer
●You were exposed to diethylstilbestrol (DES) during your mother's pregnancy
Screening recommendations for average-risk women in the United States are shown in a table (table 1).
In the past, experts recommended that every woman have a cervical cancer screening every year. This has changed. Depending on your age and how you are screened, screening is recommended every three or five years for most women over age 21.
More frequent testing may be needed if test results are not normal, or for women with human immunodeficiency virus (HIV) disease or other specific immune system conditions.
Screening recommendations for average-risk women in the United States are shown in a table (table 1).
PREPARING FOR YOUR CERVICAL CANCER SCREENING
A Papanicolaou smear (Pap test) or human papillomavirus (HPV) test can be done at any time during your menstrual cycle. Some doctors recommend waiting until your menstrual cycle has ended before doing a Pap test.
Pap test — If a Pap test was done as part of your cervical cancer screening, the results from your Pap test will be available a few weeks after your visit. Pap test results may be reported as:
●Negative – Pap tests that have no abnormal, precancerous, or cancerous cells are labeled as negative for intraepithelial lesion or malignancy.
●Abnormal results – Cervical cells may appear abnormal for a variety of reasons. For example, you may have a cervical infection or you may have a precancerous area or even cervical cancer.
HPV test — If a HPV test was done as part of your cervical cancer screening, the results will be available a few weeks after your visit. The results may be reported as:
●Negative – There are no high-risk HPV strains present.
●Positive – There are high-risk HPV strains present.
Follow-up testing — If your Pap or HPV test is abnormal, you may need follow-up testing; the best strategy depends on several individual factors.
Follow-up for abnormal Pap tests is discussed separately:
WHERE TO GET MORE INFORMATION
Your healthcare provider is the best source of information for questions and concerns related to your medical problem.
This article will be updated as needed on our website (www.uptodate.com/patients). Related topics for patients, as well as selected articles written for healthcare professionals, are also available. Some of the most relevant are listed below.
Patient level information — UpToDate offers two types of patient education materials.
The Basics — The Basics patient education pieces answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials.
Patient education: Cervical cancer (The Basics)
Patient education: Cancer screening (The Basics)
Patient education: Human papillomavirus (HPV) vaccine (The Basics)
Patient education: Pap tests (The Basics)
Beyond the Basics — Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are best for patients who want in-depth information and are comfortable with some medical jargon.
Patient education: Follow-up of low-grade abnormal Pap tests (Beyond the Basics)
Patient education: Follow-up of high-grade abnormal Pap tests (Beyond the Basics)
Patient education: Management of a cervical biopsy with precancerous cells (Beyond the Basics)
Patient education: Genital warts in women (Beyond the Basics)
Patient education: Human papillomavirus (HPV) vaccine (Beyond the Basics)
Patient education: Colposcopy (Beyond the Basics)
Professional level information — Professional level articles are designed to keep doctors and other health professionals up-to-date on the latest medical findings. These articles are thorough, long, and complex, and they contain multiple references to the research on which they are based. Professional level articles are best for people who are comfortable with a lot of medical terminology and who want to read the same materials their doctors are reading.
Cervical cancer screening tests: Techniques for cervical cytology and human papillomavirus testing
Cervical cytology: Evaluation of atypical and malignant glandular cells
Cervical cytology: Evaluation of high-grade squamous intraepithelial lesions (HSIL)
Cervical cytology: Evaluation of low-grade squamous intraepithelial lesions (LSIL)
Preventive care in adults: Recommendations
Screening for cervical cancer
Screening for cervical cancer in HIV-infected women and adolescents
The following organizations also provide reliable health information.
- Koutsky LA, Ault KA, Wheeler CM, et al. A controlled trial of a human papillomavirus type 16 vaccine. N Engl J Med 2002; 347:1645.
- Villa LL, Costa RL, Petta CA, et al. Prophylactic quadrivalent human papillomavirus (types 6, 11, 16, and 18) L1 virus-like particle vaccine in young women: a randomised double-blind placebo-controlled multicentre phase II efficacy trial. Lancet Oncol 2005; 6:271.
- International Collaboration of Epidemiological Studies of Cervical Cancer, Appleby P, Beral V, et al. Carcinoma of the cervix and tobacco smoking: collaborative reanalysis of individual data on 13,541 women with carcinoma of the cervix and 23,017 women without carcinoma of the cervix from 23 epidemiological studies. Int J Cancer 2006; 118:1481.
- Wright TC Jr, Cox JT, Massad LS, et al. 2001 Consensus Guidelines for the management of women with cervical cytological abnormalities. JAMA 2002; 287:2120.
- American College of Obstetricians and Gynecologists. ACOG Practice Bulletin number 66, September 2005. Management of abnormal cervical cytology and histology. Obstet Gynecol 2005; 106:645.
All topics are updated as new information becomes available. Our peer review process typically takes one to six weeks depending on the issue.