Human papillomavirus in 2019: An update on cervical cancer prevention and screening guidelines
Release date: March 1, 2019
Expiration date: February 29, 2020
Estimated time of completion: 1 hour
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ABSTRACT
The human papillomavirus (HPV) causes most cases of cervical cancer. Healthcare providers can help prevent this cancer by recommending HPV vaccination when appropriate, regularly screening women for cervical cancer, and following up on abnormal test results.
KEY POINTS
- Immunization against HPV can prevent up to 70% of HPV-related cervical cancer cases.
- Gardasil 9 is the only HPV vaccine currently available in the United States and is now approved for use in males and females between the ages of 9 and 45.
- In girls and boys younger than 15, a 2-dose schedule is recommended; patients ages 15 through 45 require 3 doses.
- Vaccine acceptance rates are highest when primary care providers announce that the vaccine is due rather than invite open-ended discussions.
- Regular cervical cancer screening is an important preventive tool and should be performed using the Papanicolaou (Pap) test, the high-risk HPV-only test, or the Pap-HPV cotest.
Is there a best screening protocol?
The USPSTF reviewed large randomized and observational studies to summarize the effectiveness of the 3 screening strategies and commissioned a decision analysis model to compare the risks, benefits, and costs of the 3 screening algorithms. The guideline statement notes both cotesting and high-risk HPV testing offer similar cancer detection rates: each prevents 1 additional cancer per 1,000 women screened as opposed to Pap-only testing.19
Also, tests that incorporate high-risk HPV screening may offer better detection of cervical adenocarcinoma (which has a worse prognosis than the more common squamous cell carcinoma type). However, both HPV-based screening strategies are more likely to require additional colposcopies for follow-up than Pap-only screening (1,630 colposcopies required for each cancer prevented with high-risk HPV alone, 1,635 with cotesting). Colposcopy is a simple office procedure that causes minimal discomfort to the patient.
The USPSTF guideline also differs in the recommended frequency of high-risk HPV-only testing; a high-risk HPV result should be repeated every 5 years if normal (as opposed to every 3 years as recommended by ACOG and ASCCP).19 The 5-year recommendation is based on analysis modeling, which suggests that performing high-risk HPV-only testing more frequently is unlikely to improve detection rates but will increase the number of screening tests and colposcopies.19
,No trial has directly compared cotesting with high-risk HPV testing for more than 2 rounds of screening. The updated USPSTF recommendations are based on modeling estimates and expert opinion, which assesses cost and benefit vs harm in the long term. Also, no high-risk HPV test is currently FDA-approved for every-5-year screening when used by itself.
All 3 cervical cancer screening methods provide highly effective cancer prevention, so it is important for providers to choose the strategy that best fits their practice. The most critical aspect of screening is getting all women screened, no matter which method is used.
It is critical to remember that the screening intervals are intended for patients without symptoms. Those who have new concerns such as bleeding should have a diagnostic Pap done to evaluate their symptoms.
Follow-up of abnormal results
Regardless of the pathway chosen, appropriate follow-up of any abnormal test result is critical to the early detection of cancer. Established follow-up guidelines exist,22,23 but accessing this information can be difficult for the busy clinician. The ASCCP has a mobile phone application that outlines the action steps corresponding to the patient’s age and results of any combination of Pap or HPV testing. The app also includes the best screening algorithms for a particular patient.24
All guidelines agree that cervical cancer screening should start at age 21, regardless of HPV vaccination status or age of sexual initiation.17,18,25 Screening can be discontinued at age 65 for women with normal screening results in the prior decade (3 consecutive negative Pap results or 2 consecutive negative cotest results).23
For women who have had a total hysterectomy and no history of cervical neoplasia, screening should be stopped immediately after the procedure. However, several high-risk groups of women will need continued screening past the age of 65, or after a hysterectomy.
For a woman with a history of stage 2 cervical intraepithelial neoplasia or higher grade lesions, routine screening is continued for an additional 20 years, even if she is over age 65. Pap-only testing every 3 years is acceptable, because the role of HPV testing is unclear after hysterectomy.23 Prior guidelines suggested annual screening in these patients, so the change to every 3 years is notable. Many gynecologic oncologists will recommend that women with a history of cervical cancer continue annual screening indefinitely.
Within the first 2 to 3 years after treatment for high-grade dysplastic changes, annual follow-up is done by the gynecologic oncology team. Providers who offer follow-up during this time frame should keep in communication with the oncology team to ensure appropriate, individualized care. These recommendations are based on expert opinion, so variations in clinical practice may be seen.
Women infected with the human immunodeficiency virus can have Pap-only testing every 3 years, after a series of 3 normal annual Pap results.26 But screening does not stop at age 65.23,26 For patients who are immunosuppressed or have a history of diethylstilbestrol exposure, screening should be done annually indefinitely.23
