Over the past 4 decades, deaths from cervical cancer in the United States have more than halved. However, new research suggests that previous estimates may have underestimated women's risk of death from disease.

[A cervical cancer diagnosis]
A new analysis suggests that death rates from cervical cancer may be higher than previously thought.

Study co-author Anne Rositch, Ph.D., of the Johns Hopkins Bloomberg School of Public Health in Baltimore, MD, and colleagues report their findings in the journal Cancer.

Cervical cancer is a cancer that starts in cells that line the cervix.

This year, it is estimated that there will be around of invasive cervical cancer diagnosed in the U.S., as well as approximately 4,210 deaths from the disease.

According to the American Cancer Society, deaths from cervical cancer have reduced by more than 50 percent over the past 40 years, which is largely due to an increase in cervical screening.

The , however, suggests that in the U.S., women's risk of dying from cervical cancer may be significantly higher than previously estimated, particularly for black women.

Cervical cancer mortality up to 77 percent higher than previous estimates

Rositch and colleagues used 2002-2012 data from the National Center for Health Statistics and the NCI Surveillance, Epidemiology, and End Results Mortality Database to estimate cancer mortality rates.

The team notes that previous estimates of cervical cancer mortality using this data included women who had undergone a hysterectomy and who were, therefore, no longer at risk for cervical cancer.

For the new analysis, the researchers used the Behavioral Risk Factor Surveillance System to pinpoint the number of women who had undergone a hysterectomy in the U.S. between 2002-2012, and these women were excluded from the final estimates.

The new estimates revealed that the cervical cancer mortality rate for white women in the U.S. stood at 4.7 per 100,000 between 2000-2012, which is 47 percent higher than the 3.2 per 100,000 previously estimated.

Among black women, the team estimated the cervical cancer mortality rate to be 10.1 per 100,000 - 77 percent higher than the previous estimate of 5.7 per 100,000.

The researchers also found that the previous estimates of differences in cervical cancer mortality between black and white women were underestimated by 44 percent.

Furthermore, the new analysis revealed that cervical cancer mortality rates among white women had fallen by 0.8 percent annually between 2002-2012, while rates among black women fell by 3.6 percent annually.

Racial disparities in cancer mortality remains a problem

According to Rositch, the new data suggests that racial differences in cervical cancer mortality are narrowing, but that it should remain a key area of focus.

"In addition, many of those who are dying are over the age of 65, a cutoff point where guidelines generally no longer recommend women with cervices be regularly screened for cervical cancer," Rositch notes.

In an linked to the study, Dr. Heather Dalton, of Arizona Oncology, and Dr. John Farley, of St. Joseph's Hospital and Medical Center - both in Phoenix, AZ - say that the new estimates highlight the "vexing problem" of racial disparities in cancer mortality across the U.S., but there are positive indications.

"The mortality gap between black and white women appears to be narrowing, especially among women in their 20s and 30s," they write. "This may be an early sign of the impact of HPV vaccination."

Drs. Dalton and Farley add:

"Access to adequate cervical cancer screening and preventive care remains critical to eliminating the racial disparity. HPV vaccination should continue to be emphasized among communities and healthcare providers."

Learn about a report that discusses the global disparities in breast and cervical cancers.