Rx For Change: Racial Disparities in Cervical Cancer Mortality

By Sophia King

Cervical cancer was once the leading cause of cancer death for women in the U.S.1 The vast majority (91%) of these cancers are caused by chronic infection with specific strains of the human papillomavirus (HPV).2 Typically, our immune system eliminates HPV before cancer develops.3  If the virus isn’t eliminated, prevention and early detection strategies play a significant role in limiting cervical cancer morbidity and mortality.3

Cervical cancer is one of few diseases for which early screening procedures identify precancerous tissue, using a Pap test, prior to cancer development.1 4 U.S. annual cervical cancer incidence and mortality have declined by more than 75 percent due to HPV vaccinations and regular Pap test screening. 1 3 9  Disturbingly, however, race is a strong predictor for the development of cervical cancer in this country, and Black women, in particular, have disproportionately higher risks for developing the disease.2, 4  5

Given the availability of prevention and screening strategies,6 why are cervical cancer incidence and mortality rates higher among Black women and other women of color? The answer reflects problems with documentation, prevention, and detection strategies.

In 2020, an estimated 13,800 women were diagnosed with cervical cancer and 4,290 women died.7 But, mortality rates have historically been underestimated, because cancer registries often do not adjust their data to account for women without a cervix.8 U.S. hysterectomy rates are highest among Black women, so the underestimation has the most profound impact on statistics specific to women of color.8 When women without a cervix are included in cervical cancer data, death rates for Black women over age 20 rise from 5.7 to 10.1 deaths per 100,000 women.8  For white women, cervical cancer death rates increase from 3.2 to 4.7 deaths per 100,000 women.8 Without this adjustment, the disparity between Black and white women’s deaths from cervical cancer were underestimated by 44 percent.8 To improve survival rates, we must first provide accurate statistics about this disparity.

A second obstacle in preventing and treating cervical cancer involves economic barriers to gynecologic care.9 Low-income women in the U.S. (including the 24 percent of Black women who live below the poverty line) are less likely to be able to access health care, including cervical cancer screening.10 Challenges in accessing basic health services may also impact an individual’s immune system, hindering clearance of HPV infections.3 In addition, many of the states that have not expanded Medicaid and access to care for lower-income residents have large Black populations.11 Until basic health care, precancer surveillance, HPV vaccination, and cervical cancer treatment are widely available to women of all economic levels, this disparity will persist.

Because most cervical cancers are detectable using routine Pap test screening, the U.S. Preventative Task Force (USPTF) recommends all women aged 21-65 get tested every 3 years.6  Surprisingly, given their increased mortality from cervical cancer, Black women have the highest rate of Pap screening of any racial/ethnic group in the country; 85.4 percent of U.S. Black women had a Pap test in the last 3 years, vs. 82.5 percent of white women.6 8 9 12 Even so, women of color are dying at twice the rate as white women.6 8 9 12

This higher mortality rate stems from loss to follow-up after an abnormal Pap test, as well as being diagnosed later with cervical cancer (called “late-stage diagnosis”).8 9 Unfortunately, late-stage diagnoses result in much lower survival rates.9 Women diagnosed with early (local) cervical cancer have a 92 percent chance of survival after 5 years; survival rates decrease to 17 percent for women with a late (distant) cancer diagnosis.9 For this reason, risk-reduction efforts must look beyond initial Pap screening. Addressing barriers to cancer prevention strategies, and increasing access to, and utilization of, follow-up treatment are vital to reducing racial disparities in cervical cancer’s incidence and mortality.

HPV vaccination protects against most cervical cancer types, but only works when people receive the full series of vaccinations.6 13 After release of Quadrivalent Gardasil (the first HPV vaccine approved in the U.S.) cervical cancer incidence among vaccinated women fell from 55.2 to 33.3 percent between 2008 and 2014.6 13 14 Unfortunately, Black women are the least likely of any racial/ethnic group to get fully vaccinated.13 Compared to white women, 18-to-30-year-old women of color are 30 percent less likely to receive the initial Gardasil vaccination, and 25 percent less likely to complete the series.13  Barriers to vaccination include limitations in insurance coverage, lack of information about the value of the HPV vaccine, and fear and mistrust of the health care system.9 

In addition, Gardasil was initially less effective at protecting Black women overall.13 Of the 40+ HPV strains, 14 are high-risk for developing cervical cancer.3 For reasons that are unclear, Black and white women tend to acquire different high-risk HPV strains.5 White women are more likely to get strains 16, 18, 39, 56, and 66; Black women are more likely to get strains 33, 35, 45, 58, and 68.5  

The first version of Gardasil offered protection against 4 HPV strains: 2 low-risk types (6 and 11) and 2 high-risk types (16 and 18).5 Black women are two times less likely to carry these specific high-risk strains compared to white women.5 Only after 2014, when a 9-valent version of Gardasil was released that included 2 HPV strains that are more prevalent among Black women, could they benefit broadly from vaccination.5 6 Women who received the earlier version of Quadrivalent Gardasil may not be as protected as they think.

Cervical cancer is now practically preventable. Vaccination and routine Pap testing have contributed to an overall, consistent, decrease in cervical cancer since 1950.9 14 But, current approaches are failing women of color, particularly Black women. To improve outcomes, we must supply accurate statistics regarding cervical cancer; expand access to, and knowledge about, HPV vaccination; improve follow-up after abnormal Pap tests; and decrease economic, environmental, educational, and personal barriers to cervical cancer treatment. 

Reducing cervical cancer disparities requires a comprehensive approach; fortunately, we have the knowledge and tools necessary to provide solutions. We know which prevention and treatment practices work. We also know who is most in need of help. The next step is to act and, given the persistent disregard for women of color in the United States, it’s long past time to do so. In the interest of a country that prides itself on the promise of equality, any effort to achieve that promise should engage all pursuits in life—health included. 

Sophia King is a Cancer Research Training Award recipient for the National Cancer Institute. She received her Master of Science in Health and the Public Interest from Georgetown University, and was an undergraduate student-athlete at the University of Connecticut.

References

  1. Centers for Disease Control and Prevention (CDC), Cervical Cancer Statistics. Atlanta (GA): CDC, 2020; Available from: https://www.cdc.gov/cancer/cervical/statistics/index.htm.
  2. Centers for Disease Control and Prevention (CDC), HPV-Associated Cancer Rates by Race and Ethnicity, Atlanta (GA): CDC, 2020. Available from: https://www.cdc.gov/cancer/hpv/statistics/cervical.htm.
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  10. Black Demographics, Black Women: Statistics. 2020; Available: https://blackdemographics.com/population/black-women-statistics/.
  11. Kaiser Family Foundation (KFF), Status of State Medicaid Expansion Decisions: Interactive Map, San Francisco (CA): KFF, 2020. Available from: https://www.kff.org/medicaid/issue-brief/status-of-state-medicaid-expansion-decisions-interactive-map/.
  12. National Center for Health Statistics (NCHS), Centers for Disease Control and Prevention, National Vital Statistics System, Mortality Data. Atlanta (GA): NCHS, 2020.
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