Cervical Cancer Screening Options: What Is Best For You?

Cervical Cancer & HPV

Jared Hirschfield & Varuna Srinivasan, MBBS, MPH, National Center for Health Research

Smiling women

Cervical cancer is cancer in the cells lining the cervix, the narrow passage between the uterus and vagina. This cancer is usually diagnosed in women between the ages of 35 and 44.1 Each year approximately 13,000 women in the United States are diagnosed with cervical cancer and 4,700 women die from cervical cancer.2 With regular screening and follow-up, however, cervical cancer is one of the easiest cancers to prevent and is highly curable if found early.

Almost all cases of cervical cancer are caused by the human papillomavirus (HPV), most commonly by two high-risk strains called HPV-16 and HPV-18.3 However, nine out of ten HPV infections go away on their own without treatment and do not result in cancer or any other health problems.

In addition to exposure to HPV-16 and HPV-18, there are other traits and behaviors that increase your chances of developing cervical cancer, including:4

  1.     Smoking
  2.     Multiple sexual partners and sexual intercourse at an early age
  3.     Obesity
  4.     In utero exposure to DES, a hormonal medication banned by the FDA in 1975
  5.     Long-term use of oral contraceptive pills
  6.     Multiple pregnancies
  7.     Other sexually transmitted diseases, such as HIV and chlamydia
  8.     Poor dietary habits that can increase inflammation or weaken the immune system
  9.     Family history of cervical cancer

Screening for cervical cancer

There are three screening methods to help detect and diagnose cervical cancer early when it is easy to treat. These include Pap smears, HPV tests, and a combination of both Pap smears and HPV tests (cotesting).

The United States Preventive Services Task Force (USPSTF) is a group of experts that regularly updates its recommendations for cervical cancer screening. In its 2021 update, the USPSTF clarified that for women aged 30 to 65, all three screening strategies are considered equally acceptable: a Pap smear every 3 years, high-risk HPV (hrHPV) testing every 5 years, or Pap smear and HPV cotesting every 5 years.5 The term ‘high-risk HPV test’ refers testing for the strains most likely to cause cancer, including HPV 16 and HPV 18 and several others. When most people talk about getting an “HPV test,” they’re usually referring to this “high risk” test. For women aged 21 to 29, they recommend Pap smear (also called Pap test or cytology) alone every 3 years. They do not recommend screening for individuals under 21. They also do not recommend screening for women over 65 or women who have had a hysterectomy (removal of the uterus), if they have no history of high-grade cervical lesions or cervical cancer and have had adequate prior testing. These recommendations apply to individuals with a cervix who do not have symptoms, regardless of their sexual history or HPV vaccination status. The American College of Obstetricians and Gynecologists (ACOG) and the Society of Gynecologic Oncology (SGO) have endorsed and adopted these recommendations.

USPSTF Cervical Cancer Screening Recommendations (Updated August 2021)5

Women younger than 21 years

No screening
Women aged 21 to 29 years

Pap smear alone every 3 years*
Women aged 30 to 65 years

Any one of the following:

•   Pap smear alone every 3 years

•   FDA-approved primary HPV testing alone every 5 years

• Cotesting (HPV testing and Pap smear)
every 5 years
Women older than 65 years

No screening after adequate negative prior screening results
Hysterectomy with removal of the cervix

No screening in individuals who do not have a history of high-grade cervical precancerous lesions or cervical cancer

*These recommendations apply to individuals with a cervix who do not have any signs or symptoms of cervical cancer, regardless of their sexual history or HPV vaccination status.

What is a Pap smear?

A Pap smear is used to evaluate abnormal cells in the cervix that can be diagnosed as pre-cancer or as cervical cancer. When a woman undergoes a Pap smear, a doctor or nurse collects cells from the outer layer of the cervix with a special stick, swab or a soft brush. The sample is then sent to a lab, where a pathologist checks for signs of abnormal cells. If the test is “positive,” the woman has abnormal cells, and those are graded, from least severe to most severe, as ASC-US (atypical squamous cells of undetermined significance), LSIL (low-grade squamous intraepithelial lesion), ASC-H (atypical squamous cells, cannot rule out HSIL), or HSIL (high-grade squamous intraepithelial lesion). Based on this grade, your doctor might recommend further testing, such as a colposcopy (a procedure in which the cervix is examined with a magnifying instrument) or a cervical biopsy.

What is an hrHPV test?

In a high-risk HPV test, also known as an hrHPV test, cells collected from the cervix are tested for the presence of HPV-16 and HPV-18, types of HPV that are most likely to cause cervical cancer. Keep in mind, however, that unlike the Pap smear, the HPV test does not tell you whether you have cervical cancer or are likely to develop cervical cancer. Instead, it can only tell you if you currently have the virus that can be dangerous now or in the future.3

Which screening test is better?

The goal of both screening tests is to detect cervical cancer as early as possible while keeping the risks to women at a minimum. Pap smears and HPV testing accomplish this in different ways. Whereas Pap smears identify abnormal cells currently in your body, HPV testing indirectly measures your risk of precancer or cancer by identifying the presence of the virus. HPV testing itself is not harmful, but testing for a virus that usually goes away by itself can lead to a very high rate of false positives.6 This means that people who may never actually develop cervical cancer may undergo expensive and painful invasive procedures to test for cancer and will experience the stress and fear of a cancer diagnosis.

Women with more than one sexual partner in recent years or whose sexual partner has other sexual partners are especially likely to have HPV. For that reason, the National Center for Health Research (NCHR) recommends a Pap smear every 3 years rather than an HPV test for these women. Alternatively, NCHR recommends combining a Pap smear and HPV test every 5 years. In addition, we recommend that women over 65 who have recently had more than one sexual partner or have had a sexual partner who has had other sexual partners should continue regular Pap smears until age 75.

You may wonder why the experts prefer different screening tests at different ages and have no preference for the different types of screening during most of women’s adult years. It’s because research indicates that each of these screening tests have advantages and disadvantages. HPV tests may find the virus earlier, but they also find a lot of infections that would never cause cancer. This can lead to many women getting a follow-up procedure called a colposcopy, which is uncomfortable, stressful, expensive, and not always needed. For example, an analysis by the U.S. Preventive Services Task Force (USPSTF) found that using the HPV test alone could lead to about 766 colposcopies for every 1,000 women screened—while Pap smears alone led to only 39 colposcopies for every 1,000 women screened, and both screening methods were similarly effective at saving lives.7 Other studies found that co-testing (Pap smear plus HPV test) compared to HPV testing alone prevent about the same number of deaths, but the number of tests and procedures (and costs and anxiety) may be higher with co-testing.8 Most of these studies were done in Europe, where a positive HPV test is not usually followed by immediate colposcopy, but rather by cytology (Pap smear). After that, if cytology is normal, repeat HPV testing is typically done after 12 months.9,10 We agree that this seems like a logical way to maximize the benefits of these two different types of tests, instead of doing them together. Another reason why research results vary is that many of the studies didn’t look at actual cancer outcomes but instead focused on early warning signs of abnormal cells, that don’t always lead to cancer.11

Bottom line: What is the best screening option for screening and how can cervical cancer be prevented?

The USPSTF recommendations are based on assumptions about the sexual activity of women at different ages. On average, women over 30 tend to have fewer sexual partners and more monogamous relationships than women under 30, and women over 65 have even fewer. However, the National Center for Health Research recommendation is focused more on the number of sexual partners, and the fact that women in a monogamous relationship do not necessarily know if their sexual partner has had any other sexual partners. For that reason, we recommend Pap smears every 3 years or Pap smear-HPV cotesting every 5 years as the preferred methods of cervical cancer screening for most sexually active women aged 30 to 75. Pap smears directly determine the presence of cancerous or precancerous cells in your body. Cotesting can provide the added benefit of identifying high-risk HPV infection and allow for more vigilant follow-up if HPV-16 or HPV-18 is diagnosed.

Cervical cancer is one of the few cancers that can often be prevented if it’s found early through regular screening. That’s why it’s so important to focus on active screening—finding problems before they become serious. When changes in the cervix are caught early, they can be treated before they turn into cancer. But if people don’t get screened at that early stage, the cancer might only be found after it spreads, when it’s much more difficult and more expensive to treat. Regular Pap smears, HPV testing, or both can help catch early signs before they become dangerous. Preventing cancer is always better than having to cure it—and active and staying up to date with screening gives people the best chance to stay healthy.

In addition to monogamous relationships, women can reduce their chances of cervical cancer by using condoms. Other ways of reducing the risk include regular screening and follow-up with your physician, exercising, maintaining a healthy weight and balanced diet, and avoiding tobacco products.

References:

[1] American Cancer Society. “Key Statistics for Cervical Cancer.” 04 January 2018. https://www.cancer.org/cancer/cervical-cancer/about/key-statistics.html.

[2] U.S. Food and Drug Administration. (2023, January 11). Cervical Cancer 101: What Every Woman Needs to Know. https://www.fda.gov/consumers/knowledge-and-news-women-owh-blog/cervical-cancer-101-what-every-woman-needs-know

[3] Centers for Disease Control. “Cervical Cancer.” December 2016. https://www.cdc.gov/cancer/cervical/pdf/cervical_facts.pdf.

[4] American Cancer Society, What Are the Risk Factors for Cervical Cancer?, www.cancer.org, https://www.cancer.org/cancer/cervical-cancer/causes-risks-prevention/risk-factors.html, October 3rd 2018

[5] American College of Obstetricians and Gynecologists. (2021). Updated cervical cancer screening guidelines: Practice advisory. https://www.acog.org/clinical/clinical-guidance/practice-advisory/articles/2021/04/updated-cervical-cancer-screening-guidelines

[6] Rebolj, M. et al. “The Problem of False-Positive Human Papillomavirus DNA Tests in Cervical Screening.” Current Pharmaceutical Design (2013) 19: 1439. https://doi.org/10.2174/1381612811319080011

[7] U.S. Preventive Services Task Force. Cervical Cancer: Screening. Draft Recommendation Statement. 2021. https://www.uspreventiveservicestaskforce.org

[8] Felix JC, Chilakapati R, Parvu V, et al. The Clinical and Economic Benefits of Co-Testing Versus Primary HPV Testing for Cervical Cancer Screening: A Modeling Analysis. J Women’s Health. 2016;25(6):606–616.

[9] Rijkaart DC, et al. Human papillomavirus testing for the detection of high-grade cervical intraepithelial neoplasia and cancer: final results of the POBASCAM randomized controlled trial. Lancet Oncol. 2012;13(1):78–88. doi:10.1016/S1470-2045(11)70296-0

[10] Maver PJ, Poljak M. Primary HPV-based cervical cancer screening in Europe: implementation status, challenges, and future plans. Clin Microbiol Infect. 2019;25(11):1350–1356. doi:10.1016/j.cmi.2019.09.006

[11] National Center for Health Research. Comments on USPSTF’s Draft Recommendation Statement on Cervical Cancer Screening. 2024. https://www.center4research.org/nchr-public-comment-uspstf-cervical-cancer-screening-2025/