U.S. Cervical Cancer Rates Higher Than Previously Reported, Particularly Among Older Women and African American Women
Cervical cancer rates in the United States are higher than previously believed, particularly among 65- to 69-year-old women and African American women, according to a study by Rositch et al published in Cancer. Current U.S. cervical cancer screening guidelines do not recommend routine Pap smears for women over 65 if their prior test results have been normal.
Previous Studies Failed to Correct for Hysterectomy
Previous research found an age-standardized rate of about 12 cases of cervical cancer per 100,000 women in the United States, with the incidence reaching a peak at age 40 to 44 and then leveling off. However, these estimates included women who had hysterectomies in which the cervix was removed. By excluding these women, who are no longer at risk of developing this cancer, from their analysis, the researchers calculated a rate of 18.6 cases of cervical cancer per 100,000 women. They found the incidence increased steadily with age and peaked at a higher rate and at an older age, specifically in women 65 to 69 years old.
“The higher rates of cervical cancer after correction for hysterectomy highlight the fact that, although a large proportion of cervical cancer has been prevented through early detection and treatment, it remains a significant problem,” the authors concluded. Human papillomavirus (HPV) infections cause nearly all cervical cancers, and the researchers stressed the need for widespread HPV vaccination to protect women against the virus.
Study Details
The researchers analyzed data on cervical cancer from 2000 to 2009 from 18 registries within the Surveillance, Epidemiology, and End Results (SEER) program of the National Cancer Institute (NCI), part of the National Institutes of Health. The data in the 18 registries represent approximately 28% of the U.S. population. The researchers generated estimates of hysterectomy prevalence from the Behavioral Risk Factor Surveillance System, a household survey conducted by the U.S. Centers for Disease Control and Prevention.
The incidence of cervical cancer for women aged 65 to 69 was 27.4 cases per 100,000 women, 84% higher than the uncorrected rate of 14.8 cases per 100,000 women. Among white women aged 65 to 69, the rate was 24.7 cases per 100,000, compared with an uncorrected rate of 13.5 cases per 100,000. The rate for African American women aged 65 to 69 was 53 cases per 100,000, compared with an uncorrected rate of 23.5 cases per 100,000.
In fact, African American women had higher cancer rates at nearly all ages compared with white women, and the disparity was more pronounced at older ages, likely attributable to African American women reporting a higher prevalence of hysterectomy than white women.
Screening Implications
“Our corrected calculations show that women just past 65, when current guidelines state that screenings can stop for many women, have the highest rate of cervical cancer,” said the study’s lead author, Anne F. Rositch, PhD, MSPH, an Assistant Professor of Epidemiology and Public Health at the University of Maryland School of Medicine and a researcher at the University of Maryland Marlene and Stewart Greenebaum Cancer Center. “It will be important to consider these findings when reevaluating risk and screening guidelines for cervical cancer in older women and the appropriate age to stop screening.”
The researchers said that failing to correct for hysterectomies not only underestimates the true incidence of cervical cancer but also results in misleading race- and age-specific comparisons.
Dr. Rositch added, “It will be important to clarify in future studies whether the continued increase in cervical cancer rates with age and the higher rates in African American women represent a failure in our screening programs or a failure of the women to be screened so that appropriate interventions can be applied.”
Dr. Rositch is the corresponding author and Patti E. Gravitt, PhD, of the University of New Mexico Health Sciences Center, is the senior author of the Cancer article.
The research was supported by the NCI, the Institutional Research Cancer Epidemiology Fellowship funded by the NCI, and the Career Development Award for Bridging Interdisciplinary Research Careers in Women’s Health.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
