Cervical Cancer Screening (PDQ®)–Health Professional Version
SECTIONS
- Overview
- Description of the Evidence
- Evidence of Harm
- Changes to This Summary (06/14/2018)
- About This PDQ Summary
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Overview
Note: Separate PDQ summaries on Cervical Cancer Prevention, Cervical Cancer Treatment, and Levels of Evidence for Cancer Screening and Prevention Studies are also available.
Screening With the Papanicolaou (Pap) Test: Benefits
Based on solid evidence, regular screening of appropriate women for cervical cancer with the Pap test reduces mortality from cervical cancer. The benefits of screening women younger than 21 years are small because of the low prevalence of lesions that will progress to invasive cancer. Screening is not beneficial in women older than 65 years if they have had a recent history of negative test results.[1-3]
Magnitude of Effect: Regular Pap screening decreases cervix cancer incidence and mortality by at least 80%.
- Study Design: Population-based and cohort studies.
- Internal Validity: Good.
- Consistency: Good.
- External Validity: Good.
Screening With the Pap Test: Harms
Based on solid evidence, regular screening with the Pap test leads to additional diagnostic procedures (e.g., colposcopy) and treatment for low-grade squamous intraepithelial lesions (LSILs), with long-term consequences for fertility and pregnancy. These harms are greatest for younger women, who have a higher prevalence of LSILs, lesions that often regress without treatment. Harms are also increased in younger women because they have a higher rate of false-positive results.
Magnitude of Effect: Additional diagnostic procedures were performed in 50% of women undergoing regular Pap testing. Approximately 5% were treated for LSILs. The number of women with impaired fertility and pregnancy complications is unknown.
- Study Design: Evidence obtained from cohort or case-control studies.
- Internal Validity: Good.
- Consistency: Good.
- External Validity: Good.
Screening With the Human Papillomavirus (HPV) DNA Test: Benefits
Based on solid evidence, screening with the HPV DNA or HPV RNA test detects high-grade cervical dysplasia, a precursor lesion for cervical cancer. Additional clinical trials show that HPV testing is superior to other cervical cancer screening strategies. In April 2014, the U.S. Food and Drug Administration approved an HPV DNA test that can be used alone for the primary screening of cervical cancer risk in women aged 25 years and older.[4]
Magnitude of Effect: In one prospective, clustered, randomized trial, HPV testing was superior to other strategies for preventing cervical cancer mortality.[5,6]
- Study Design: Clustered randomized controlled trial (RCT).
- Internal Validity: Good.
- Consistency: Good.
- External Validity: Good.
Screening With the HPV DNA Test: Harms
Based on solid evidence, HPV testing identifies numerous infections that will not lead to cervical dysplasia or cervical cancer. This is especially true in women younger than 30 years, in whom rates of HPV infection may be higher.
Magnitude of Effect: In one study, 86.7% of women with a positive HPV test did not develop cervical cancer or related premalignant disease after more than a decade of follow-up.[7]
- Study Design: Long-term observational trials.
- Internal Validity: Good.
- Consistency: Good.
- External Validity: Good.
Screening With the Pap Test and the HPV DNA Test (Cotesting): Benefits
Based on solid evidence, screening every 5 years with the Pap test and the HPV DNA test (cotesting) in women aged 30 years and older is more sensitive in detecting cervical abnormalities, compared with the Pap test alone. Screening with the Pap test and HPV DNA test reduces the incidence of cervical cancer.[3]
Magnitude of Effect: HPV-based screening provides 60% to 70% greater protection against invasive cervical carcinoma, compared with cytology.[8]
- Study Design: RCTs.
- Internal Validity: Good.
- Consistency: Good.
- External Validity: Good.
Screening With the Pap Test and the HPV DNA Test (Cotesting): Harms
Based on solid evidence, HPV and Pap cotesting is associated with more false-positives than is the Pap test alone. Abnormal test results can lead to more frequent testing and invasive diagnostic procedures.[3]
Magnitude of Effect: The percentage of U.S. women undergoing cotesting who will have a normal cytology test result and a positive HPV test result (and who will therefore require additional testing) ranges from 11% among women aged 30 to 34 years to 2.6% among women aged 60 to 65 years.[3]
- Study Design: RCTs.
- Internal Validity: Good.
- Consistency: Good.
- External Validity: Good.
Screening Women Without a Cervix
Based on solid evidence, screening is not helpful in women who do not have a cervix as a result of a hysterectomy for a benign condition.
Magnitude of Effect: Among women without cervices, fewer than 1 per 1,000 had abnormal Pap test results.
- Study Design: Evidence obtained from a single cohort study.
- Internal Validity: Good.
- Consistency: Good.
- External Validity: Good.
References
- Sasieni P, Castanon A, Cuzick J: Effectiveness of cervical screening with age: population based case-control study of prospectively recorded data. BMJ 339: b2968, 2009. [PUBMED Abstract]
- Sawaya GF, McConnell KJ, Kulasingam SL, et al.: Risk of cervical cancer associated with extending the interval between cervical-cancer screenings. N Engl J Med 349 (16): 1501-9, 2003. [PUBMED Abstract]
- Moyer VA; U.S. Preventive Services Task Force: Screening for cervical cancer: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med 156 (12): 880-91, W312, 2012. [PUBMED Abstract]
- Wright TC, Stoler MH, Behrens CM, et al.: Primary cervical cancer screening with human papillomavirus: end of study results from the ATHENA study using HPV as the first-line screening test. Gynecol Oncol 136 (2): 189-97, 2015. [PUBMED Abstract]
- Sankaranarayanan R, Nene BM, Shastri SS, et al.: HPV screening for cervical cancer in rural India. N Engl J Med 360 (14): 1385-94, 2009. [PUBMED Abstract]
- Szarewski A: Cervical screening by visual inspection with acetic acid. Lancet 370 (9585): 365-6, 2007. [PUBMED Abstract]
- Chen HC, Schiffman M, Lin CY, et al.: Persistence of type-specific human papillomavirus infection and increased long-term risk of cervical cancer. J Natl Cancer Inst 103 (18): 1387-96, 2011. [PUBMED Abstract]
- Ronco G, Dillner J, Elfström KM, et al.: Efficacy of HPV-based screening for prevention of invasive cervical cancer: follow-up of four European randomised controlled trials. Lancet 383 (9916): 524-32, 2014. [PUBMED Abstract]
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